Archive of Our Own ^beta

Chapter Text

Tobirama did not appreciate it when children were in danger. A personal code, some would say. A symptom of growing up seeing children die in wars they had no business fighting. 

Truthfully, those reasons would probably be it if his main reason wasn't because his kind were obsessed with children. Instinct demanded he protect and shelter pups at any and all costs. Not that he knew that at first. 

It was rare for him to see shinobi in his waters. The Land of Iron wasn't known for its high number of clans. It was more populated by samurai and their lords than any shinobi clans. There were a few shinobi natives, sure, but they were very reclusive. Shinobi in Iron were skilled at using chakra to climb the mountains and travel through the countless underground tunnels that pocketed its landscape. They rarely dared touch the rivers that branched through their mountains. 

Most of the waterways in Iron Country were more treacherous than the mountain peaks. They were often full of rushing whitewater and steep drops. The snowmelt made them cold and hypothermia inducing. 

And if you were particularly unlucky, you could be swept down into the underground rivers by the powerful currents. The tunnels down there could stretch for dozens of miles of dead ends. Tobirama had found countless bodies and remains of people who had been sucked down. 

These threats were all perfectly harmless for Tobirama of course. Whitewaters were his preferred terrain. The tunnels proved little risk with his sensing keeping him from getting lost and his gills keeping him from drowning. And while his body wasn't as good at adjusting to the sheer cold, he simply spent the coldest months further south in upper Fire Country where nothing could find him. 

He spent the majority of the year in the Dokuishi River hunting fish or the occasional land animal and avoiding humans like the plague. On occasion he traded his fins for human feet and traded smoked and salted fish for goods in nearby villages as he had for years. He'd lived that way since he was six years old and tossed out of his family for growing said fins. 

Butsuma had at least been too concerned with the ill luck killing a “water yokai” like him might have brought the Senju to kill Tobirama at the time. Instead he'd dragged him suffocating in the dry air to toss into the Naka, telling him to begone or he would kill him, bad luck or no. 

Tobirama, too used to the thin line his poor health had always given him with his Father's patience, knew he was not bluffing. So he'd swam as fast as he could as far as he could on new fins he didn't know how to use. 

The Naka hadn't been safe, too surrounded by humans as it was. He'd been spotted several times. Once when Tobirama was nine and feeling awfully lonely, he'd drifted too close to the Senju's territory. It didn’t take too long before he saw Butsuma running up the river with murder in his eyes. Tobirama fled. The human had chased him for eight hours until he finally stopped. 

Tobirama hadn't gone back since. 

Things had been challenging, but he'd made do. He's survived. Then he'd worked hard and done what he had to do - more than just survive - until he'd carved something of a life out for himself in the Dokuishi. 

While he didn't often encounter humans near the rivers in Iron, he did occasionally have to rescue one lost or stuck in the current from some accident. Sometimes he was too late and had to place the corpses where someone might hopefully find it “washed up”. (A very large part of Tobirama wanted to eat them, because free meat. The part of him that still walked around on human legs wrinkled his nose at the idea and so he did not.) 

The locals knew of him thanks to his occasional rescue. Mouryou no Shirochi, they called him. White Bloody Water Spirit. Not very creative. But his white colorless scales combined with the few accents of bright red did inspire an intimidating figure to the few who glimpsed him. 

He may or may not have used his human form (hair colored brown with dirt and hiding his red eyes behind overgrown tangles) to sneakily encourage neutral tales of that creature. At least two small villages along the Dokuishi had shrines set up for him that he shamelessly raided. He was not a malicious ‘spirit’ unless provoked. And many people were comfortable with such spirits so long as they were in fact not provoked. So nobody came to look for him. Or bothered him. Generally, in fact, humans didn't encroach on his territory at all. Many went far out of their way to not even pass over this stretch of the Dokuishi. 

(He was fairly certain he wasn't a yokai or spirit of any sort. He'd yet to find out what exactly quantified as a yokai. “A creature beyond normal knowing, not a summons creature, and with abilities not explained by chakra.” was what he had settled at as the best definition. He for the most part did not count as a yokai. The only one of his abilities that couldn't be explained was his ability to change forms between human and scaled beyond biological explanation. So… he was probably not a yokai.

At the very least, Tobirama was most certainly not a mouryou, known for their dark skins and grave robbing to eat rotting corpses. His urge to eat human bodies was purely an instinctive drive to eat free food. He felt the same urge when some animal was killed trying to cross the river. And he certainly did not like eating rotting meat. It made him sick. He only did so as a young child when very desperate and hungry.

The people who knew of him still referred to him as a mouryou, though. Perhaps a kinder version because of his white scales. Tobirama sighed and let them call him what they may so long as they left him alone.) 

This encounter was a first, for Tobirama. This time there were shinobi running along the less violent stretch of water. To cover their trail, he would assume. A good strategy ordinarily. But not one that would last on the Dokuishi as any native would know. 

As he predicted, eventually the waters became too rough to walk on and the men gathered on the riverbank to discuss their route. 

Tobirama was prone to boredom. Stalking humans who lingered by the river was not out of the ordinary, for him. He grabbed onto a rock with his limbs and allowed his tail to drift downcurrent as he listened in. They did not expect anyone to be around- and water carried sound very well against the rocky shores. Even with the whitewater nearby to muffle them, he could hear them very well indeed. 

He did not need to listen for long before his fins straightened out and he had to restrain his snarls of fury. 

They had a child. A child they had taken, injured and bleeding, and were talking about being ordered to bring to an employer. 

Tobirama's instincts were rarely easy to brush aside. When they said to nest, he nested. When they said to prepare for torpor, he headed south. When they said to nest and lay empty eggs, he found the warmest waters possible and did as instinct commanded. When they said he was hungry, it did not matter if he was trying to ration his food, he ate. 

When his instincts demanded harder than anything else he'd ever felt that he slaughter each of the three men responsible for kidnapping a child, Tobirama didn't stand a chance. His mind went blank. 

He was only vaguely aware of letting go of the rock he'd clung to and spinning around, swimming upstream. Gathering space. Then twisting back around and swimming at top speed with the current to back him. He exited the water with a piercing whistle that echoed ferociously against the ravine walls. 

His large tail catapulted him out of the river at speeds fast enough that when he slammed into one of the men, he heard bones crunch underneath him wetly. The man was left gasping through his own blood, in shock and dying slowly on the ground as Tobirama turned to the other two. 

He pushed off the ground with powerful legs that climbed waterfalls with ease. Crooked, clawed fingers dug into the shinobi's throat before he could do more than pull out a kunai. 

The remaining shinobi held the bound pup to his chest, backing up with horror on his face. 

Tobirama bared all of his curved teeth at the man, a clicking hiss coming from deep in his chest. 

He swiped with one arm. Water exited the river in a spear, nearly stabbing the human. The bastard dodged the sealless jutsu and then turned to run. He turned his back to him. 

Tobirama got him with the second spear. The pup toppled to the ground as the man did. 

He whistled worriedly, immediately crawling across the ground to pull the pup away from the threat. He made sure to slice each man's throat. Then turned to the pup wriggling its way across the bank as best as possible while still tied. 

Tobirama clicked in amusement at the clever pup. But not necessary. He crawled over and turned the pup over, checking for injury. 

The pup cried out, cringing away from him. 

Tobirama cooed soothingly, hovering over it. He could wait for the pup to calm. It would be some time before his gills dried out and he could merely douse himself with water when they did. 

He wasn't sure how long it took for the pup to relax. It stared at him with wide, wide eyes. Then- 

“H-hello?” The pup whispered, fear in its voice. 

Tobirama cooed again, laying on his stomach and his head on his arms. He whistled softly until the pup stopped trembling, tail idly flipping across the ground. 

“M-my name's… Kagami. Thank you for saving me.” The pup did its best to give a polite bow, shaky and nervous as it was. He whistled, charmed. 

The pup watched him. He watched the pup. Slowly the pup examined him. All twelve feet of him. Half if it was tail, but still. Tobirama would not deny he flared his fins proudly and showed off the red-tipped scales on his tail. 

The pup eventually stopped staring at him and began to struggle with the ropes still binding it. 

Tobirama chirped gently, reaching his claws forward. The pup froze up again until he slowly picked the ropes into pieces. 

(Part of him demanded he take the rope for later, for supplies. Tobirama did not waste anything. That part of him was buried behind pup pup pup pup-) 

Kagami pup stood up, legs shaking. It sniffled. Tried to not look at the dead humans. 

Tobirama cooed at it supportively. The pup looked to him again and then paused. Its dark eyes widened. 

“You're hurt!” Kagami pup said, hands reaching out awkwardly. 

Tobirama looked down. His chest hurt. The second human had hit him with a kunai. It was a fairly superficial blow. He hadn't even noticed it in his rage. Peeled some scales off, which hurt a lot, but wasn't serious. It did bleed but only sluggishly. 

He clicked assuringly and crawled over. The pup looked concerned. 

He cooed again until the pup relaxed. Then he tugged the pup by its sleeve towards the water. No need to grab it and frighten it more. 

Kagami pup resisted, making worried noises, but did eventually end up ankle deep in water. It shivered and pulled away. 

“It's too cold!” Kagami pup said, frightened despite his best efforts to soothe it. 

Tobirama clicked angrily. Right… right. Humans… humans couldn't handle cold water so well. Pups couldn't either. Pups needed bright warm waters. 

No. He needed to stop thinking with his hindbrain. Humans didn't live in water. 

But his nest was not just water. His nest had plenty of dry portions. Kagami pup would still be plenty safe there. 

He nodded to himself. It would take some time, but he'd take Kagami pup to his nest the long way then. 

Tobirama crawled his way into the water and swam upstream. He stayed in the shallows, even as it was awkward to maneuver his long tail. Once he went a ways, he stopped and chirped at the pup. 

Kagami pup stumbled along the rocky riverbank after him after a few confused starts. Tobirama chirped encouragingly. 

It took a long time. Many hours later, in fact, and Kagami had to stumble to a rest at one point. Tobirama crawled up onto the bank to churr at it comfortingly until it felt strong enough to get up again. 

Finally they made it to his nest. Tobirama could duck in through the water passage easily. Kagami pup shouldn't enter the cold water, though, so he exited the water and crawled the distance to his backup entrance. The pup followed after him slowly. 

The entrance was hidden by trees and reeds. Tobirama squeezed through and chirped until Kagami pup followed once more. 

Down the tunnel they went until they reached the cavern Tobirama had been living in for many years now. A large space with plenty of room for him when he did not have fins and a shallow pool with his nest, leading out a tunnel to the waterfall for his finned form. He chirped proudly, crawling towards his rarely used nest on land. It was more a place for him to relax in human form than to sleep. He preferred sleeping in the water. 

“Woah.” Kagami pup said slowly as it looked around in the low light. It allowed Tobirama to guide it to the nest, tucking it in amongst the blankets. 

He fetched food immediately, smoked fish and dried fruits he traded for in the village. He'd been just about to leave for the winter so had no fresh food stored. Just his emergency stock. Kagami pup ate eagerly as he grabbed his rarely used waterskin. The pup drank deeply. 

Tobirama took one of its hands as it continued to eat with the other. Rope burns covered its little wrists. He churred as he did his best to heal it. His healing jutsu weren't very well practiced. Just from old memories from so long ago in the healing rooms as a pup himself. Enough to heal minor injuries, perhaps, but little else. 

The pup had plenty of little injuries. It had a few more serious ones as well, dark bruises all across its ribs and a swollen wrist. Tobirama whistled sadly over it as he wrapped them in bandages and wished he knew how to fix them. 

Kagami pup allowed him to fuss and bury it in blankets, thanking him quietly as it slowly fell asleep. The air was chilly in here but hopefully not too much for the pup if it stayed wrapped up in those blankets. 

Tobirama had to retreat to his pool soon after the pup fell asleep, curling up in his nest and chirping every now and then. 

Slowly over the course of the next hour Tobirama's mind came back to himself. He felt a tad ridiculous at how far behind his instincts he'd fallen. He'd never been around children in this form before. He had not expected.. all of that. Apparently whatever he was had some very strong instincts about children. 

The child was safe and sound though, so that was… good. He felt strangely tired. Maybe the hormonal rush? 

Well. Kagami was sound asleep, with food and water within reach if he woke up. He could take a nap of his own.

Madara was losing his mind. They'd found the bodies of the kidnappers who had taken little cousin Kagami, out gathering herbs with his aunt. They'd even killed the apothecary in the process. He'd left Izuna in charge while he helped track down the kidnappers personally. Chased the trail all the way up Fire Country and to Iron, even. 

Where they proceeded to find the kidnappers already dead. 

With the state of decay of the bodies they found, Madara could maybe guess it had been several days since their deaths. Wildlife had torn into them and muddied the waters. And with the first harsh winter chill setting in over the past few days, it was harder to estimate time of death. 

But tracking was not his specialty so he glowered by the water with sharingan activated, scanning their surroundings as his clansmen searched the corpses for signs of what happened. 

Shishomi came to him with her report, bowing briefly. 

“It's been approximately one week since their deaths. Possibly longer. It's hard to say what killed them with the half-eaten state of them, but one has crushing wounds. Another looks like suiton wounds. We found this on the bodies.” She offered a scroll to him, already open. “The only sign of Kagami is cut ropes, hopefully meaning he got away.” 

Madara scanned the scroll with disgust. Someone had hired them to kidnap a shinobi child. Any shinobi child. With an astronomical base price that would go up based on clan and possible kekkei genkai. He would have to look into the buyer, but later. Getting his clansmen back was more important. 

“Current theory is that they were betrayed by their buyers, or someone else swooped in for the contract.” Madara rolled the scroll up and tucked it in his belt. “Split up in pairs. Search for any signs. There's a village nearby?” He confirmed with one of the four clansmen who had joined him on the mission, who nodded. “I'll investigate there. See if anyone's seen any sign of him.” 

“Madara-sama,” Shishomi stopped him before he left. “It may be nothing. But one of the men had this stuck to his kunai.” 

She offered the kunai in question. Madara took it and turned it to examine the dried up scales stuck to it by old blood. Pale white, almost colorless, and nearly translucent. He'd never seen scales quite like this. Smaller than his pinkie nail. Not from anything he recognized. 

“What is it from?” He asked, as Shishomi was an excellent hunter and tracker and excelled in using her sharingan to recognize animals by the faintest trail or single patch of hair. 

“I have no idea, Madara-sama.” Shishomi looked annoyed by her lack of knowledge. “They look almost like a fish's scales, but not one I've ever seen. They don't look right. Maybe some sort of summon?” She guessed, throwing her hands up. 

Madara imagined being struck clueless in the area of her best specialty was likely driving her mad. Shishomi was a very self-assured kunoichi. 

“So there's confirmed suiton, crushing wounds that could be doton, and possible summons at play.” Madara grunted. It was confirmation the third party was shinobi, at least. 

Shishomi bowed and left to her search with her partner. Madara accepted directions to the nearby village and went on his way. 

Iron was full of steep hills, mountain paths, cliffs, and the occasional rushing river too dangerous to water walk on. Just getting to the village from their location was a hassle. Traveling here was a nightmare and Madara chafed knowing their trail may have gone cold in the time it took them to catch up.

Chapter Text

The nearby village was small. Not much to look at. He spoke to several villagers who looked at him with fear, stuttering and shying away. He was aware he was already an intimidating figure. His anger over the child kidnapping made him even more short-tempered than usual. Even as he tried to stay calm. 

Nobody knew of any strangers or travelers passing by recently. The roads were soon to close with the upcoming winter. Most people were already through with their travels, not wanting to be caught on a mountain road in an unexpected winter storm. 

Madara tried to not snarl at the villagers for their uselessness. He didn't have any leads. Even asking the villagers if they recognized the scales he had - in case it was just some local animal he and Shishomi wouldn't know - didn't give him any results. 

Until an old woman approached, eyes wary. The others had merely glanced at the scales and shrugged. She narrowed in on them before he could even speak to her and grabbed Madara's sleeve, tugging him along to her house. Confused - and out of options - he let her. 

“Tsumiki!” She rasped, opening the door. “Tsumiki, come see!” 

A young woman hurried to the door to see them with confusion, eyes widening when she saw Madara looming in her doorway. 

“H-hello, sir. Can I help you? Mother, what is this?” She tried to pull her mother away from him worriedly. The old woman went with only a mutter. 

“Look, look Tsumiki, see if you recognize these scales shinobi-san has brought.” 

Madara held out the patch of scales wordlessly. The woman, Tsumiki apparently, leaned over to look. She gasped. 

“Mouryou no Shirochi.” Tsumiki breathed, awe evident. “Sh-shinobi-san, where did you find these?” Her hands cradled Madara's with reverence, not as if afraid to touch him but… the scales. 

“You recognize them?” He asked instead of answering her question. 

“Y-yes, the color is so distinct- the only thing that would fit more is if it were the red on its tail-” Tsumiki hurried to back away, ushering him and her mother to sit down inside. “Please, shinobi-san, where did you find them?” 

“On the weapon of a trio of dead shinobi,” Madara grunted as he settled in a chair that creaked ominously. “Who had kidnapped a child.” 

“And they were by the water?” The old woman - still unintroduced - looked thoughtful.

“...they were.” A good guess, or she knew more than anyone else had. 

Tsumiki nodded as if that made sense, brow furrowed. 

“Those scales belong to Mouryou no Shirochi, a river spirit who haunts the Dokuishi.” Tsumiki said slowly. “It is a generally benevolent spirit. So long as it is left alone, it does not act against anyone. Many leave offerings at the bridges over its territory to honor it.” 

“And you recognize the scales because..?” Madara would hold his tongue on the validity of a yokai of all things being responsible. 

“Some years back,” Tsumiki said slowly. “Bandits raided the villages in this area. I was… one of the women they took.” Her hands trembled on the teapot she hung over the fire. “When crossing over a bridge, for whatever reason, Mouryou no Shirochi disapproved of them. The bridge collapsed. The bandits did not survive the currents. But everyone they took was brought by Mouryou no Shirochi to the shores; cold and weary but alive. There were only four of us, the other three were from Ukimi Town to the west. But we all saw glimpses of it as it saved us. White scales, with a tail tipped in red. A fearsome horn on its head. It was large and very powerful.” She laughed shakily. “I had believed in its presence before then, you don't live around deadly rivers without believing in river spirits, but I somehow did not believe in its strength before then.” 

“Mouryou no Shirochi has rescued several people from its waters over the last decade. And many have glimpsed a large white creature amidst the waters.” The old woman said. “We knew of its guardianship of its waters since it first appeared, but the bandits were the first time it had ever killed. Thirty some men lost to the river. Whatever they did to displease it has been a worry of many.” She grinned, crooked yellow teeth half gone. “Many won't even use the bridges at all anymore, afraid that it is displeased by men crossing its waters. With my Tsumiki and the other girls having lived, I'm more sure Mouryou-sama disapproved of the evil men crossing its waters rather than any man. Or perhaps it only allows women to cross.” She cackled lowly. 

“That is one theory.” Tsumiki said, bringing cups and what Madara could already tell were poor quality tea leaves. “There are many, in regards to Mouryou no Shirochi. But everyone respects its territory regardless.” She tilted her head. “It does hibernate, in winter, as we never see sign of it once the first snow hits. This may be the last any of us hear of Mouryou-sama until spring. The child was likely rescued like many others. Though where they were taken, I'm unsure.” She frowned worriedly. “Most rescued by Shirochi are left near bridges, where they can find help along the road. Some say that those too heavily injured to move or unconscious are left in plain sight, with piercing screams calling for help until someone arrives. But we've heard nothing of a child found along the river.” 

She looked very worried. Madara was too. If this was actually a spirit… it was possible it was one of the spirits that craved children. He hoped and prayed the scales were merely from a summons of some sort. 

He stayed for tea, weak as it was, and listened to Tsumiki and her mother Mizuno tell tales of the yokai. Some were just tales. Others were stories directly from the mouths of those rescued. As one of those women herself, Tsumiki had met many other people who'd directly or indirectly encountered the spirit. They all made frequent treks to the shrines set up at the bridges to offer thanks to Mouryou no Shirochi for their lives. 

Madara had something of a lead, at least. He could check the shrines and any villages or towns nearby for more rumors. Maybe ask about the hermit he was told traveled nearby, see if he'd heard anything. People regularly turned up unconscious or injured at the shrines. If Kagami was safe, he could be there. Or someone may have heard something. 

There was a knock on the door partway through a tale of Mouryou no Shirochi being glimpsed near a shrine, sleeping in the shallow water during summer. It was apparently known to like sunlight and warmth. Which could make sense if it slept through winter. 

Hiroto was at the door, breathing hard. Shishomi's partner. 

“Madara-sama.” He nodded his head. “Shishomi found a trail.” 

They were gone less than a minute later, Madara thanking the two women for their assistance and leaving behind a few coins. They left before either could protest the payment. 

While he still wasn't certain of the validity of claims of a yokai, they hadn't lied. Something large and white lived in the river that regularly rescued people. Their information was worth a few yen.

Madara followed Hiroto back towards the river. Several miles up it, actually. 

Shishomi had found a child's bare footprints in a patch of sand. Further up the river, she'd found more in some mud. All very faint. Alone. No sign of anyone else. 

Kagami may have gotten free on his own, then. Madara breathed in relief as he filled the two of them in on his own findings. Less helpful as they were, it meant once they found Kagami that they ought to seek out the shrines for Mouryou no Shirochi and leave an offering in thanks. It cost very little to honor and appease the spirits. 

Shishomi found more signs of a trail, muddled on harsh river stones that hid marks, but every now and then she found something the rest of them couldn't see. Enough to keep going.  

They followed the river looking for more tracks until they came up to a waterfall. Madara blinked up at the harsh cliff with a curse. They'd followed the river from here. From here the trail would likely be harder to follow. Should they climb the cliff and seek more clues up above? Or split up to search both directions along the cliff? Could Kagami have even climbed the cliff on his own, barefoot and tired? 

“Madara-sama,” Shishomi found a patch of mud with numerous footprints. Pieces of fish scales. 

He blinked and activated his sharingan, cataloging the entire clearing below the waterfall. Someone came here frequently. Might even live nearby. After some searching the area they found a smoking pit, half-buried. Maybe the hermit he'd heard about? 

He'd almost split them up to look for him when there was a cry that had all their heads snapping up. 

“MADARA-SAMA!” 

Kagami yelled as he ran through the foliage, crashing into Madara as he sank to his knees to grab him. He looked the boy over worriedly as Kagami cried and sniffled. Signs of bruising and small injuries mostly healed. The only real injury was his wrist, wrapped tightly in torn cloth. 

Madara breathed out slowly in relief, pressing his cousin's forehead to his own. The back of his head fit in Madara's palm. He was so small and fragile. 

There was nothing to be said about it. Kagami would have to live with him and Izuna in the Head House, from now on. He refused to let the boy out of his sight. 

Kagami wiggled and struggled to be put down. “Madara-sama, you have to help Rochi-sama! He's sick!” 

Rochi-sama? The hermit, maybe? “Who is Rochi-sama?” Madara refused to put Kagami down. 

“Mouryou no Shirochi-sama, he's a river spirit and he saved me and brought me here and he's sick he won't wake up when I try to talk to him!” Kagami wriggled fiercely, deeply upset. 

Considering this was probably the most he'd heard Kagami say since his parents’ death last year, Madara was a little taken aback. Then surprised it was actually the river spirit. Then worried that the spirit had taken Kagami instead of leaving him by the riverside. 

“Where is Mouryou-sama?” Madara asked carefully. 

Kagami pointed. “The cave- you go in over here if you can't swim.” 

Madara debated heavily what to do from here. Yokai could be very dangerous when provoked. He didn't want to offend it if at all possible. His clan owed this creature a debt and you did not stint yokai unless you wanted to be very thoroughly fucked over. 

But also, he really wanted to just grab Kagami and run back to Fire Country before the spirit could possibly claim Kagami as payment for the debt. 

“Hiroto, Shishomi- go find the other team. I will speak with Kagami-kun's rescuer.” He took a deep breath. 

Kagami took no time in pointing him to the entrance of the cave system, cleverly hidden against the cliff face without any chakra. Madara had to turn sideways and put Kagami down to squeeze his shoulders through the entrance. The tunnel from there widened out so he could at least hold Kagami's hand. He protested the treatment but settled for dragging Madara as fast as he would let him go. 

The tunnel opened up into an entire living space. It was dark but a few thin threads of light came through, presumably, cracks in the cliff wall. Whatever, or whoever, lived here clearly had been living here for a long time. There were bookshelves filled with scrolls and books. A rickety handmade table with papers and writing implements. A stained brown haori hung across the back of the chair at the table. Storage spaces. Furs and blankets. Signs of life. 

Kagami pulled him right to the pool of water that took up a corner of the cave. He crouched by the water without fear. 

“Rochi-sama!” He called, worry obvious in his voice. 

There was a strange clicking sound that came from the water. Madara, sharingan activated to see clearly in the dim cave, shuddered as he saw the chakra curled up in the water. The shape he could discern from the chakra coils visible was unlike any creature he'd ever seen. Shaped like a man, with an incredibly large tail curled up around it. Under the water as well, which was disturbing with the human-shaped part. 

“Hello, Mouryou no Shirochi-sama.” Madara said respectfully, wanting to keep his distance but staying alert in case the creature tried to grab Kagami. 

The chakra coils stilled dangerously and then uncoiled out of the water, rising to the edge with a dangerous hiss. A human-shaped upper body rose from the water. 

“It's okay, Rochi-sama, this is my cousin Madara-sama! He came to find me!” The boy assured, fearlessly allowing the creature to bend forward over him. The creature growled. Hesitated. Wavered. Visibly calmed at least a bit. “I'm glad you're awake!” Kagami said, hugging the yokai around the neck before Madara could move. 

Shirochi swayed a bit, nuzzling into Kagami before letting out a strange churr and sinking back down into the water. 

“...yyy… you… leav-vving..?” The creature’s voice rasped, startling Madara. It slurred weakly. As if injured or drunk. 

Kagami looked to Madara, little eyes wide. “I… I want to go home…” He looked guilty towards the yokai. “Is that okay..? I'm sorry I can't stay when you're sick…” 

The creature gave an oddly… cute sounding trill, sinking further into the water. Only its arms and head remained above water, laid on the ground as if napping. 

“...nnnnot ssick… s'collld…” Shirochi gave a chirp. “P-puuup… sssafe..?” 

“I'll be very safe. Madara-sama would never let anything happen to me.” Kagami said, determined. “He came all this way to get me!” 

The yokai clicked again, meaningless to Madara but apparently meaning something to Kagami. He put his little hand on the creature's arm with a pat. It practically purred back. 

“Mouryou no Shirochi-sama,” Madara kneeled in the ground and bowed respectfully. “On behalf of the Uchiha clan, thank you for rescuing my kin.” 

The yokai stirred, unnaturally wide pupils staring back at him. He didn't meet them, staring firmly right above those eyes. 

“...U.. chiha…” The creature gave a small growl that made Madara stiffen. 

“Yes, Mouryou-sama.” He said. “My clan owes you a debt.” 

The eyes blinked at him dully. There was a rumble and Kagami looked worried, patting it. 

“...nnno… debt is… p-pup…” Its eyes closed, seemingly sleeping then and there. 

Madara's heart raced. An unpaid debt to a yokai would not go well. Either in his own conscience or in the eyes of the elders, if they found out. He'd rather they didn't find out about this. But he didn't know how well Kagami would stay quiet. 

“I insist, Mouryou-sama, please allow me to give gratitude for saving and sheltering my kin.” 

The yokai didn't stir. For several long minutes Madara waited. He dared to light a small katon, just a bright flame that they could see more clearly by. Chakra coils could only show so much. 

The pale creature looked fully asleep. Eyes closed, fins by the sides of its face flopped awkwardly. 

“Mouryou-sama?” No wonder Kagami thought it sick, if it had been like this. 

Fins flicked. Eyes twitched underneath closed lids. 

Kagami gave a worried whine. Its eyes snapped open instantly, clicking urgently. Wide pupils surrounded by red irises flicked first to Kagami and then slowly to Madara. 

“Mouryou-sama, please allow me to repay you for saving the life of my kin and sheltering him in his time of need.” Madara repeated. He tried not to sound impatient or angry. 

The fish-like yokai stared at him, fins on its jawline hanging unevenly. It rumbled and shook its head as if a cat waking from a nap. 

“...p-pay… p-pup ssafe…” The creature mumbled nonsensically. 

“Would you accept an offering of food as payment?” Madara tried. His only response was a rumbling sound that at the very least did not sound threatening. 

The yokai continued to keep drifting off to sleep as he tried to find something to offer it. Kagami could wake it in a heartbeat with a childish whine. But it couldn't seem to stay awake. Kagami was clearly very worried. 

He was past afraid of the yokai now and more annoyed. 

“Mouryou-sama, are you well? You were injured by the shinobi you fought.” Perhaps it had been poisoned? Or did fish yokai actually hibernate in the winter? 

It clicked, a human-like look of confusion on its face. It shifted oddly until Madara raised his light-flame up to see a patch of raw flesh on its chest. It didn't look inflamed or infected. 

“Cold. Sssslow.” Shirochi slurred, sinking back down into the water as if exhausted beyond measure. 

“The water got really cold when it started to get cold outside.” Kagami said. “What if you come back with us? The water is really warm near the forges and you can sleep there over winter!” 

Madara almost protested out loud when Kagami proposed that. The last thing he needed was to bring a spirit home. 

But it seemed curious, fins perking up. “...can ssstay w-wwith p-pup?” 

“I don't live by the forges, but I can visit you every day!” Kagami said. Madara stopped him with a hand on his head before he promised a yokai anything else. 

Shirochi's eyes landed sharply on his hand. It stared for a minute before relaxing. 

It hummed approvingly at the idea. The offer was made to a degree, and accepted to a degree. To renege on Kagami’s offer would be one hell of an insult.

Madara's mind raced on how to work this to their benefit. “The Uchiha clan can provide shelter, and warmer waters than Iron Country at least, over the winter. We offer protection over one cold season for you as payment for rescuing Kagami.” 

No promises to let it stay. 

Shirochi looked at him. Seemed to consider it. It hummed and let out a loud whistle. 

“Pup sssafe.” It rumbled pleasantly. “Yes.” And it backed away from the shore, sinking deep under the water. Madara watched its chakra disappear ominously down into the darkness of the water.

Kagami ran off. Madara yelled and ran after him, out through the long tunnel and outside to fresh air.

Chapter Text

They met the other four Uchiha outside, watching the river with wide eyes. 

Shirochi had approached the bank, looking half-asleep and not rising anything but its head above the water. The pale colorless scales were obvious in the sunlight. And the wicked horn that, from where he'd seen it nuzzle his cousin, could have ripped Kagami's throat out easily. 

It was visible now in its entirety. Ten or more feet worth of long white scales. Towards the end its tail was speckled with red crescents that made it look dipped in blood. 

Mouryou no Shirochi did not speak, or question them, as Madara whispered to his clansmen. Its red eyes tracked Kagami lazily. 

They were fortunate that this river could in fact be traced all the way back to the Naka that circled the Uchiha compound. As Madara didn't know how else the spirit would follow them. It would change their travel time drastically as the rivers were much more meandering than they'd like, but Madara sent two of them ahead to travel the faster way back to the clan and hopefully get… some sort of warning to Izuna about the weird shit they were bringing home. And hopefully something resembling a fitting shelter for a yokai. 

Kagami stayed with him, Hiroto, and Matsui. Shirochi would very likely not approve of Kagami being taken from its sight. Madara did not intend to test that theory. He was safer with Madara anyway. 

Slowly, they began to travel alongside the river. Shirochi kept pace in the water easily, visible as flashes of bright white scales near the water’s surface. Occasionally it clicked at them. In shallower water they could view it swimming lazily at their running speed, assisted by the current. That powerful looking tail could probably push it very fast if it actually needed to move. 

The fastest route back to the Uchiha compound was about a week’s travel. At this pace, with the detours they'd have to take and difficult terrain of following the river, they might end up delayed by an entire week. Madara wasn't overly pleased by this. But he didn't plan to complain where Shirochi could hear them. 

The first night, the spirit watched them from the riverbank as they set up camp within sight. Its eyes stayed locked on Kagami until the boy was fed and tucked into Madara's bedroll, where he planned to hold onto the boy to assuage his own paranoia. Once Kagami was out and snoring peacefully the spirit disappeared from sight. 

They didn't spot it until late morning, rising from the cold waters towards the bank. Travel was delayed until Madara was certain it was present. As much as it rankled to lose travel time he didn't want to risk losing track of it. 

The second night went much the same as the first. 

The third was different, as the day had begun to warm up slightly from the brief cold front. Shirochi seemed to be more active that day, swimming high enough in the water its fins breached the surface. Soaking up the sun. 

When they stopped for the night, Shirochi clicked at the shoreline until Kagami wandered over (Madara holding onto the back of his shirt). A large fish was plopped down at Kagami's feet. Mouryou-sama looked rather smug about it. 

Matsui cleaned the fish, leaving the guts and bones in reach of the river. They disappeared when nobody was looking. 

Kagami was given the majority of the fish, stuffed until he was full and snoozing once more. Then very cautiously the rest of them ate. Shirochi did not seem to disapprove. 

That day became a pattern as the cold front eased up. 

Shirochi kept pace easily as Madara decided to test its speed one day, sprinting along the riverbank at top speed. Kagami giggled in his arms and whooped. The spirit whistled in what he swore was amusement as it kept up without any sign of difficulty. 

The first major obstacle came when they hit a sharp cliff. Previous waterfalls the yokai had merely slid over the top, diving seamlessly into the pools at the bottom. Whitewaters? It navigated them flawlessly even as it disappeared from view. Hidden perfectly by the white froth. 

But this cliff was maybe a hundred feet down, with a much more shallow pool at the bottom. Madara opened his mouth to ask- something. But Mouryou no Shirochi was already climbing out of the water. 

It had been obvious it had legs, but they'd been unable to see it fully yet. Now its legs were on full display as it crawled across the ground and towards the slippery wet rocks. The waterfall sprayed them all with flecks of water, keeping Shirochi damp as it climbed down. Its large tail scraped and dragged behind it, occasionally nearly causing it to slip at its weight. 

At the bottom, it slid into the water with a simple groan. That night its eyes were much more awake and aware as they set up camp. 

“Uchiha.” Its voice was much stronger, less slurred. Perhaps a bit tired. But clear. 

Madara left the camp and approached the water, bowing respectfully. “Mouryou-sama.” 

Red eyes flickered over him warily. “Is Kagami's wrist okay?” 

“Swollen, but we'll have him looked over by the healers when we return.” Madara sat down on a large rock. “It's only sprained, according to Hiroto. Nothing serious.” 

Shirochi clicked a few times, eyelids blinking sideways. Madara startled. That was… weird. 

“...why did you rescue Kagami?” He dared ask after the creature seemed content to lay there bathing in the sunset’s warmth. 

“I…” The creature frowned to itself. Its tail flipped, swishing water. “My… kind, is very fond of children. I have never been around one before I saw those men, talking of selling a child.” It growled and Madara knew suddenly that all the sounds he'd thought had been growls most certainly were not. “I could not let a pup- a child be harmed.” It shook its head at its verbal stumble. 

“Your kind? Mouryou?” Madara prompted, definitely rudely. 

The creature glared at him before looking away, staring off down the river. “...I do not know what I am. Maybe I am a yokai. Maybe I am something else. I do not know. All I know is what I exist as, since fins sprouted and my gills first grew.” It shook its head. “You need not shelter me over winter. I am… more clear headed, now that the cold has passed. I will head to my usual winter nest and you may consider guiding me in my distracted state your debt paid off. Sleeping in that nest over winter would have possibly lost me a few fins.” 

Madara considered that. He absorbed all the creature had said. 

“The offer was made, and I will fulfill my end of the debt.” He said slowly. “But I would appreciate knowing you will not be absconding with my cousin come spring.” 

The creature flinched. “I… will endeavor not to. Seeing as I was willing to let you take him in the depths of my exhaustion, I hope I will not do something so foolish. Instinct is strong. My mind is not clear when it rears its head.” 

That would have to do, he supposed. Madara found himself much more comfortable with Shirochi speaking to him so clearly at least. 

“Uchiha…” The creature said, looking… complicated. Hopeful maybe? “The Uchiha are still at war with the Senju?” 

Madara eyed it strangely. “...yes.” Did creatures living in the middle of a remote river in Iron Country hear about Fire Country clan politics? 

Shirochi did not respond for a long few minutes, head low. It looked troubled. Uncertain. 

“...does Butsuma still live..?” It asked, with… a hint of fear? 

“Senju Butsuma died almost a year ago.” Madara said warily. “Why?” 

The creature stared out at the woods distantly. “...he chased me from my home, once. Long ago.” The creature whispered, hissing between its curved teeth. 

Madara's eyebrows went up. “Why the fuck did he do that?” 

Shirochi didn't respond. It simply pushed itself off the shore and sank into the water, looking lost. 

They only saw hints of the creature after that for a few days. Kagami was upset about it. They still found at least one or two fish a day left on the shore for their dinner, but otherwise they only caught glimpses of white scales and heard the occasional whistle to indicate it was keeping pace. 

Still. A deal was a deal. Maybe-yokai or not, Madara was determined to follow it. Mouryou no Shirochi had been relatively polite. And possibly had the Senju as a mutual enemy. 

Fuck, if it was a yokai, why had Senju Butsuma chased it away from its home? Who the hell did that? Madara had always been on the fence about the existence of spirits and he still would never do something so stupid. That was just inviting yourself to be cursed. 

It occurred to him that its story indicated the creature had possibly once lived in the Naka. Maybe even near the Uchiha compound where the river wrapped around their western side. Certainly near enough to the portion that bordered Senju and Uchiha lands. 

Though… it had said something about fins sprouting and gills growing. Had it been something else, first? Lots of yokai had stories of being normal animals before turning into spirits. 

With that in mind, the fact the creature looked very humanlike - beyond the coloring and tail and fins - was… worrisome. 

Two days from the Uchiha compound, Mouryou no Shirochi showed its face again as they set camp. Kagami ran to meet it with a happy cry. He hugged it around the torso, uncaring that it got his clothes damp. They all watched him carefully but Madara allowed them the semblance of privacy. 

“Are you okay, Rochi-sama?” 

“...merely bad memories, of the last time I came so far south. No worries, pup.” Shirochi nuzzled him with a churring sound. 

“You've been to the Naka before?” Kagami asked innocently. 

“...many years ago.” It admitted. “I used to try to stay near… but shinobi saw me, and I was young. Your age. I was afraid they would hurt me, so I fled upriver.” 

“When you were a kid?” Kagami said, worried. “Who were they? Were they really scary?” 

Shirochi didn't reply, just leaning his head against Kagami and making a cooing sound. 

“...were your parents dead too?” Kagami asked solemnly. Madara wanted to smack his forehead. This child. 

“...my mother was.” Shirochi said quietly. It didn't say anything else about a father. Instead, it wrapped its arms around Kagami in something like a hug. It churred and clicked pleasantly. Kagami didn't protest and seemed comfortable, so the adults slowly relaxed. If the spirit was going to drown Kagami it would have done in the week he'd been in its lair. 

Kagami continued to chatter for a while. (It was astonishing to hear when he'd been so quiet since his parents’ passing.) The creature just listened to him talk while making cooing and clicking sounds. Madara was starting to get a feel for what they meant. The coos only ever happened towards Kagami. The clicks and whistles could be soft - as they were towards Kagami - or much sharper. It made plenty of grumbling, chirping sounds that were tricky to translate but weren't actual growls. Madara couldn't get the sound of that one real growl out of his head. He had a feeling that if Mouryou no Shirochi was actually upset about something, they would damn well know. 

When the sun sank and everything grew dark, the air started to rapidly chill again. Sign of the weather turning cold once more. Madara made his way over to the water with a flame-light lit in his hand. He'd rather use the light than use his sharingan and have to see the creature's strangely humanlike chakra system. 

“Mouryou no Shirochi-sama,” He called until the creature slowly rose up. Already it was sluggish again. “Can I ask what sort of shelter you need over the winter?” He needed to ask before it became incoherent from cold once more. He would not be an incompetent host in this. 

The creature blinked slowly. First normally. Then a second time, with what looked like second eyelids that blinked sideways. Creepy. 

It shook itself and frowned, trying to focus. 

“...you may call me Shirochi.” It murmured. “I typically spend winters in a nest in upper Fire Country. Deep underground, hidden from humans. Not truly asleep, but not awake. Just… a spot underwater with no intruders. Sometimes I stir enough to get food.” 

“What food do you eat?” 

“...fish, mostly. Sometimes meat from animals at the river's edge.” It hesitated. Looked almost eager, but tried to sound casual. “I do enjoy human foods, though I can't eat too many plants.” 

Madara struggled to not snicker. It was very clearly angling for something. “Anything in particular?” He asked, unable to keep the amusement out of his voice. 

Shirochi looked offended. Its fins flattened back like a cat's. “...I don't often get sushi. Or human sweets…” It grumbled, a weird thrumming behind its gurgling voice. 

Madara couldn't help his smile, but managed to avoid outright laughing at the possibly-yokai. “We can do that. Anything specific you need for a nest?” 

It made a strange whistle, fins flaring, before shaking its head. “No. As long as it is covered and I can fit, I can do the rest.” The question seemed to have spooked it because it backed away into the river again. 

Madara watched it go with a snicker.

Following the Uchiha home was absolutely one of Tobirama's worst ideas. But his head had been so foggy with torpor and pup pup pup when Kagami broached the idea. And then Uchiha Madara had agreed to it and well. Everything snowballed from there. 

He'd tried to give the man an out. Tried to convince himself to just swim back up the river and leave. 

But between his instincts screaming about the pup and his head being foggy with the cold, Tobirama couldn't ignore the human side of him that wanted company. 

He didn't get to socialize much. His human form was dirty and covered up to hide his pale skin and hair. He knew he was unnatural looking to begin with. And he frequently found himself tongue-tied when he tried to speak to people, as anxious as he got about someone looking past his loose clothes to somehow see the monster he was.

Most of the villages he traded with were used to his human appearance by now. He was generally welcomed for his fish and stories of other villages. But most kept their distance from him. The ones who were friendly made his skin break out into a sweat and his throat close up in panic until he could only barely mumble words. 

To have humans looking at him, his finned form, and see him and not run screaming was… good. It felt good. And his instincts clamored to keep near the pup. Having the pup near, safe and happy, kept him from the anxiety human presence caused. 

So an offer to go with them, to stay the winter someplace warmer, where a pup would be nearby and he wouldn't have to worry about catching food for himself while half-asleep… it was practically a dream come true. Especially to actually talk to someone, to have a full conversation without cringing away or stuttering to a stop. 

He felt bad. It felt like a betrayal to follow an Uchiha to their home, to trust in one. But Butsuma had betrayed him first. Had cast him out. So he was no longer a Senju. It was how he justified it to himself, at least. 

Tobirama lingered in the water, listening to the humans talk as they'd slowed to a walk. There was the rush of footsteps and a shunshin. 

“Kagami!” 

“Izuna-ni!” Kagami cried happily. 

The reunion was sweet to hear. 

“We'll take Kagami to the healing hall, get his wrist looked at. You have a place for our guest?” 

“Uh huh. Mind telling me what the fuck you were thinking-” A smacking sound, that was probably Madara shoving his hand over Izuna's mouth. 

Tobirama obligingly perked his head above the slow moving water, eyeing the human warily. His head was very foggy right now. And the strange human had the pup. 

He wasn't aware of the growl in his chest until Kagami waved at him cheerily. 

“Bye Rochi-sama! I'll see you later, okay? I promise I'll visit you every day!” Kagami waved frantically. 

Izuna looked startled, eyes flashing into the sharingan. Madara elbowed him sharply and he yelped. 

“My brother will be polite and not offend the possibly-a-yokai.” Madara drawled, glaring at said brother as he took Kagami back. “I'll see you later as well, Shirochi. Let me know if you need anything.” 

Tobirama churred assuringly, eyeing Kagami as they left through the trees. But he ignored his instincts demanding he follow the pup and instead turned to the Uchiha left staring at him. 

He bowed his head to Izuna. “It's nice to meet you.” 

“It's nice to meet you too, Mouryou-sama.” Izuna bowed to him, seemingly trying to make up for earlier. 

Tobirama told him to call him Shirochi. He looked rather conflicted. 

The Uchiha led him further down the Naka River and to a small offshoot that looked freshly carved. It ended in a circular pond, close to the walls of the compound but out of sight to the back gate. Water flowed in one side and out the other to rejoin the river, keeping the water fresh. Both channels were barely deep enough for him to swim comfortably, though he crawled rather ungainly through a portion. 

Tobirama swam into the pond curiously. Large enough to circle even at his size. Deep enough to be able to sink to the bottom and potentially be out of sight. A tunnel further down led about fifteen feet deep at a curve, into an area he could nest in for safety. He could sense the chakra lining the mud and stone. 

“This was just made?” Tobirama clicked curiously as he examined where river plants had clearly been freshly transplanted. 

“Expanded. It used to be a third of the size. …You can tell?” 

“Chakra residuals are all over the place.” Tobirama informed him idly, senses expanded over the water. A doton user had made this. Very skillfully, actually, even if it was still so new it wouldn't be a proper pond for a while yet. He looked up to the human looking rather stone-faced. “It will do.” He assured. He'd have to go pull up river reeds and stones to arrange a proper nest down below, but it was safe enough. 

Izuna bowed. “Let me know if you need anything else. One of our shinobi will guard the pond at all times, from the wall.” 

Both as protection for Tobirama and to keep him under watch. He found he didn't much care, mind busy as he contemplated what he could use to make a comfortable spot before the water got too cold to focus. 

He knew one of said shinobi was probably following him as he went to and fro, pushing the channels to the pond a bit larger with suiton and bringing nesting materials. Stones mostly, cupped in one arm and dragged to the very bottom to form a round bowl shape. Then he followed up with the weeds and branches he needed to make a basic mattress. It wouldn't be as comfortable as his usual nest he intertwined wool blankets into, but he'd be far more comfortable this far south where the winters were much more mild. 

He couldn't remember if ponds froze over, here. That bothered him. He was born here once but… he'd forgotten. Now he was used to living under a sheet of ice in the winter. This pond was fairly shallow, and the current not too deep…

Chapter Text

His nest took most of the day to make decent. After that, Tobirama caught a few fish for his dinner and curled up contentedly. 

Kagami visited the next day, as promised. Izuna accompanied him. Tobirama crawled into the shallows of the pond and was grateful it was more stone than mud, but also wished his scales didn't have to scrape the flat rock so much. 

It turned out to be a fantastic sunbathing spot though, Tobirama realized as the sun beat down on the rock and warmed the shallow water up. The cool current kept him from being properly warm, but it was enough to have him churring pleasantly while Kagami stood knee deep in water and chattered nonstop at him. Izuna stood by the side of the pond the whole time, looking puzzled and concerned he'd drown Kagami in turn. 

Once Kagami was ushered away by his minder, Tobirama left again to get food. He'd gorged himself appropriately most of the fall. But if he wasn't going to fall directly into a torpor there was little point in going hungry just because his body had the stores for it. 

The pattern continued for a few days until the first true wave of winter hit. Tobirama expected to be left alone, mind foggy and curled up semi-comfortably in his nest. 

Instead he woke blurrily to a familiar whining sound and he swam up to check on the pup. Pup was fine, standing by the water, chattering at him. Tobirama clicked a hello and the pup tried to click back. It was silly sounding, not right in a human throat, and Tobirama cooed at the cuteness of it. He crawled up just enough to lay in the slightly warmer shallows, not hearing a word the pup said but enjoying its noises. 

When the pup left he whistled sadly and pup came right back. He clicked clicked clicked and stayed until the pup was eventually picked up by the human. 

He growled and whistled a sharp warning before the pup made its attempt at clicking back. He paused, confused. He clicked in question. The pup made what might have been an assuring coo back. 

He stared at the two humans, befuddled. Tobirama eventually came to the understanding that humans could not stay in the water. So they must go back. It was very cold. He chirruped in understanding as he sank back in the water, watching them retreat. The adult human looked wary. The pup waved at him. 

Tobirama swam back down and went back to sleep. 

The pattern repeated. Pup woke him up each day with a pleading whine of come-here and Tobirama swam up, clicking okay?okay? at it. Pup chirped okay!happy! and made many human noises at him until it was time to go. The pup learned to click better and better, until it had figured out bye!leave! and hello!where-are-you? and even accidentally stumbled on the high pitched chirp of help!help!guardian!! 

That had been a very confusing day. Tobirama had curled up around the pup’s legs where it stood in the water, growling and trying to figure out what the threat was. He vaguely remembered snarling at the other humans before pup cooed okay!okay!safe!! at him for long enough and he realized everything was okay. 

At some point, when he became too still and had not hunted in some time, the humans began to bring him food when Kagami pup visited. Tobirama ate many very, very tasty things and a few that he spit out. But mostly very tasty things. They gave him a lot of food. So much he couldn't eat all of it, with how little appetite he had in the cold. He encouraged the pup to eat what he didn't. 

Eventually he got so blurry he stopped eating. His mind only remembered hearing pup, checking on it, and then sinking back to the bottom once he saw that the pup was alright. Pup clicked and whistled worry!worry! at him until he cooed an annoyed okay!okay! 

But unlike past winters, he never stopped waking entirely. Every time the pup called for him he answered. Even if it was just to check on the pup. 

Snow and ice covered his nest and Tobirama curled up, wishing for blankets to intertwine with. He answered the pup's cries of hello!where-are-you? with a tired whistle and stayed below. Even when someone  broke the ice, pup didn't whistle danger, so he assumed all must be well. 

At some point when he rose to the surface, called by the pup when the water was less cold, he found pup with blankets that it offered to him. He churred happily and claimed them, chirping as he arranged them in his nest. Much more comfortable. 

Winter passed in a blur of tasty snacks and gifts. Tobirama had never felt so giddy. Even deep in the fog of torpor he felt touched that Kagami still came every single day the weather permitted. And when the weather was too much, one of the adult Uchiha would show up and give clumsy attempts at okay?okay? until he whistled back at them. 

The months passed quickly as they always did for him in torpor. But slower, this time, as he was continually woken and prodded into responding. 

Spring arrived and he stirred. The shallow pond meant the water in his vicinity warmed up very fast. But the snowmelt coming from upriver meant the Naka itself stayed very cold. 

He was woken by a cheerful chirp. Stretching, Tobirama realized he felt… mostly awake and aware. The past weeks he'd slowly been waking more and more. Finally - barring late frosts - he should be mostly out of torpor season for now. 

Tobirama surfaced with a pleased chirp back at the pup. It was impressive that he'd learned so many of the instinctive noises Tobirama had always known. 

“Hi Rochi-sama!” Kagami said, pulling his little hakama up to wade into the water. “Madara and I brought you fish today! Are you hungry?” 

“Not as much as I usually am this time of year.” Tobirama rumbled, tongue slurred from misuse. 

Kagami gasped and charged into the water to hug him. Tobirama whistled in surprise. “You're awake!! Rochi-sama, you're awake!!” 

“Mmm. The pond is warm enough, yes.” Tobirama nuzzled the boy, hugging him back briefly before pulling his clingy arms away from his primary gills he needed to breathe with. 

“It’s good to hear you again, Shirochi.” Madara crouched by the water, a wooden plate with strips of meat in his hand. 

He churred pleasantly. When Madara scooted the plate closer pointedly he crept up the shallow stone to eat. 

“Usually by this point,” He said after eating, still hungry but sated for now. “I'm half-starved. Thank you, sincerely, for the assistance.” 

“It was our honor.” Madara nodded firmly. “Do you know when you will be leaving to your territory?” He asked pointedly, though not unkindly. Kagami whined at the idea of him leaving. 

Tobirama considered the chill of the current pushing water into his- into the pond. “What month is it?” 

“It's mid March.” 

He blinked. That was much earlier than he usually woke. He said so. “The waters up in the mountains won't be warm enough until late April, at the earliest. I can leave for my usual winter nest in… a week’s time?” 

“You may stay until your home waters are suitable.” Madara allowed, graciously. 

Then again, he'd found out that Kagami was actually near directly related to him. So his gratitude at the boy's safety couldn't be understated. 

Still Tobirama thanked him sincerely.

Spring was a tricky time for Tobirama, usually. Finding food to get himself back in shape was a necessity. Easy enough when fish were even slower than him to wake from torpor, but still a challenge. Going back home was a huge hassle as well. Opening up everything to air out, checking none of the waterways had changed while he was gone, and beginning to work on getting his first catch of fish to trade for the supplies he'd need at the start of his year was a lot of work. 

This year was very different. The extra time let him catch plenty of fish to give to the Uchiha in thanks. The shallow pond and its perfect sunbathing spot gave him several sunburns as he soaked up the sun. Thankfully the damage wasn't brought up by the humans who watched him or he'd feel terribly embarrassed. 

More often than not, Izuna became his general watcher. He kept pace with him from the water's surface as he explored the Naka near the compound. Tobirama introduced him to the spots along the river that the fish were beginning to spawn in, so the Uchiha knew where to avoid overfishing. Izuna turned out to be a fairly talkative person and sunbathed on the shore nearby whenever Tobirama did, the two of them talking and helping with his usual anxiety of talking to people.

It was early April when Tobirama tasted something strange in the water. The rain falling made for heavy waters and overrun river banks. Perfect for Tobirama to stretch his fins unseen under dark clouds. 

He didn't have a current watcher. The Uchiha were beginning to trust him and they only guarded over the pond unless he invited someone along to accompany him for one reason or another. 

He swam upriver trying to follow the source of the taste until it became stronger. Familiar. 

Human blood. 

Tobirama hurried, finding a human body facedown floating in the current. Nobody he knew. And with no sign of being an Uchiha. He dragged the body to shore and tossed it out of reach for someone to look at later. The water still tasted strange. He continued up river. 

He found a human hiding in the water, breathing raggedly. He churred quietly as he approached through the thick reeds. 

The human gasped and cringed in on himself, until he held his hands up. 

“Do not scream.” He told the Uchiha man quietly. “I am an ally. What happened?” 

The man stared at him, wide eyed. Tobirama bit back the urge to hiss impatiently and just laid green glowing hands on his wounds. He didn't know enough to do more than clean up the injuries. Couldn't do anything about the blood in his lungs. But he could help a little bit. 

The man fought down a cough. “H-Hagoromo. Betrayed us. Attacked a patrol.” He rasped. “Need to get to the compound-” He almost choked, trying to keep his cough quiet. 

Tobirama churred at him carefully. “They are still in Uchiha territory?” He cursed how his sensing was so limited in this form. One of the truest advantages of human form was how far his sensing reached. 

The man nodded, tired and pale and likely a bit delirious. 

“...I will need your kimono.” Tobirama said. 

Five minutes later he'd swam at top speed to the pond, the Uchiha emblazoned kimono clutched in his claws. He crawled out of the water and onto shore, shifting and unable to stop the full body shudder as he metaphorically peeled back his scales and fins to reveal human skin. The sensation was always strange and uncomfortable. But he didn't have time to scratch at where his scales ought to be. 

Didn't have time when he could now sense numerous chakra signatures gathered to the northeast. Approaching. Laced with malice. Intent to kill. 

He put the kimono on and stumbled to his feet, shaky after months with fins. He pulled his hair over his face where he could and stumbled towards the compound. 

The rain was coming down so hard it was likely the guard couldn't even see the pond. But a white haired figure coming up to a foot of the walls was most certainly visible.

“Halt!” Matsui landed on the ground, sword drawn and looking alarmed. 

“It's me, Shirochi.” Tobirama held his hands up, voice clearer than it ever was in his other form. Human language was much easier without fangs. “There's a problem- an Uchiha patrol was downed upriver, a survivor hiding in the reeds. The Hagoromo attacked them and are still around.” 

Matsui stared at him. His eyes visibly cataloged the Uchiha kimono, the white hair and pale skin. 

“Stay.” He demanded, shunshining to the top of the compound wall and calling for someone. Matsui jumped back down and motioned him to follow, heading towards the back gate. 

Madara and Izuna both met them at the gate, eyes calculating. 

“You can be human?” Izuna blurted. He looked like a wet cat under the pouring rain. 

“I was human first.” Tobirama grumbled. “I can't in the winter.” For a variety of reasons but- “It doesn't matter right now. The Hagoromo attacked an Uchiha patrol upriver. I can sense a group of chakra signatures gathering seven miles to the northeast, approaching slowly and spread out.” 

“How many signatures?” Madara snapped. 

“You can sense chakra seven miles away?” Izuna said, startled. 

“Seventeen people. I can sense very far, in human form. Not in my other form. I only knew something was wrong when I tasted blood coming downcurrent.” He answered both of them, feeling dizzy. 

Madara sharpened. He turned and shouted for someone named Hikaku. The compound lit up in a frenzy within minutes, more strong chakra signatures flaring in one spot than Tobirama had felt in decades. He felt dizzy from it all and stumbled when Izuna ordered him to follow him. 

The ground swayed under his feet and he found himself in Izuna's arms, the man shaking him and calling his name. 

“Shirochi? Shirochi!” He shook him. “Are you hurt?”

“Nnno. Chakra. A lot. So many.” Tobirama slurred, mind struggling to… stay. It felt like he was falling apart. 

“Shit. Right. You're a damned sensor.” 

It scared him. It felt like he was five years old again, back when he still had a big brother and two little ones. When Mother died and the world had exploded in chakra everywhere and he'd had to focus in on Hashirama's mountain of energy or he'd float away like a leaf on the wind. When his sensing had first woken and he'd been in so much pain, lost, overwhelmed by too much. 

Chakra around him, worried, confused. He was moved and felt an arm under his shoulders hauling him around. Walking barefoot through the mud and stumbling in his clumsiness. He threw up at one point. Then he was laid down and a familiar chakra signature popped up, burningcoals flaring brightly next to him. 

“Rochi-sama?” Kagami whispered. 

“How did you-? No, Kagami, you don't need to be in here-” 

Tobirama whined in protest. Kagami's chakra flared strongly. The little sensor flickered and dodged to get near him. He latched onto the bright little chakra as a lodestone. Desperate, trying to ignore the rest of the chakra around him. 

Someone pulled the ill-fitting kimono off of him and dried him off, wiping mud away and putting clean clothes on him. He was left alone after some time, Izuna lingering nearby as Kagami snuggled into his side. 

Tobirama felt like the ground was swaying underneath him as he fought to stay centered. This was the other reason he rarely interacted with humans. In human form, his sensing was too strong and he tended to get overwhelmed even in small towns. 

The Uchiha compound was more than big enough to count as a village in itself, but the problem was how shinobi had massive chakra signatures compared to the civilians Tobirama was used to living near. He whimpered as chakra flared in combat to the north. Kagami clicked assuringly at him and he couldn't help a strangled laugh. 

“I can't even make those noises in human form.” He said, unable to open his eyes because they insisted he was laying down while his chakra felt like he was bobbing in a current. 

“Are you feeling any better?” Kagami asked quietly. 

“Somewhat.” Tobirama rasped. “I'm sorry I scared you.” He pressed his chakra up against his in apology. 

“It's okay. I feel too much sometimes too.” 

“Wait- what do you mean by that, Kagami?” Izuna asked, inching closer. 

Kagami was quiet, burrowing into Tobirama's side. 

“...did you not know he was a sensor?” Tobirama squinted his eyes open to look at the Uchiha in confusion. 

The horror on Izuna's face said that no, they didn't know Kagami was a sensor. 

Tobirama closed his eyes with a sigh. “I'd love to help.” He said tiredly. “But I never got any training of my own. I use my other form to block my sensing when overwhelmed.” More like his sensing changed forms rather than was blocked, but there weren't any human chakra signatures in the river for the most part. And when there were they didn't need to be there. 

“You said,” Izuna said slowly. “That you were human first.” 

He hugged Kagami close. “I was born human, as far as I know. When I was six years old I grew fins and gills. My… clan did not approve of a yokai in their midst. My sensing had already developed at the time, but I was still too young to have trained it any.” He explained quietly. Tobirama didn't even care if they threw him out or tried to kill him. He was comfortable in his ability to defend himself when his element was literally pouring out of the sky and he was very, very good at running from humans at this point. 

“Huh.” Was all the man said. 

Slowly Tobirama managed to relax, focused on Kagami's tiny spark of chakra to ignore the fighting happening several miles away. If Izuna attacked him, he would flee. Until then… he would try to keep himself from drifting off.

At first Izuna had been reasonably cautious of the yokai. Then confused. Then he'd realized Shirochi would probably murder them all to protect Kagami, and that Kagami had him wrapped around his little finger. After that Izuna managed to realize that, possibly-yokai or not, Shirochi was just a strange fish man who liked to talk about books and take naps in the sun. They'd kind of become friends after he'd come out of his foggy winter state. 

Seeing the human shape in front of him now, Izuna realized that yeah, he was just a guy. He looked the same age as him even. Long white hair was still damp from the rain, hiding his face from view. His eyes were red when he squinted between white eyelashes. Pale skin, skinny as all hell, and looking particularly sad and pathetic when Izuna had dragged him into the healing halls. 

“How old are you?” Izuna couldn't help but ask. 

Shirochi frowned and asked what year it was. Izuna hated what that implied. Then he answered. 

“Nineteen, then.” 

Yeah no, Shirochi was only one year older than him. 

Putting it all together made a lot of sense. Madara had shared everything he knew about Shirochi with Izuna and vice-versa as they both found out more and more. Just to stay on top of the strange fish maybe-yokai they'd both been getting familiar with. 

Senju Butsuma had once chased Shirochi from his home. Likely with extreme force. 

Shirochi claimed he'd been born human, and his clan hadn't liked when he turned out to not be. 

Easy conclusion was that Shirochi had been a Senju before being chased out. Ordinarily that would piss Izuna the fuck off. But… he couldn't help but imagine how awful that must have been. 

Six years old. Kami, Izuna couldn't imagine how heartless Butsuma was to chase a fucking six year old child out of house and home. It was the previous generation that had kept up the child-hunters, so he supposed Shirochi ought to be grateful Butsuma hadn't just killed him. 

Just another fucking reason to hate Butsuma and rest of the old guard. Izuna wanted to spit at the thought. Fucking Senju bastards. 

Well. Clearly, Shirochi didn't have any negative feelings towards Uchiha, or he would have never rescued Kagami. Or maybe he would've ripped Madara's throat out when they first met and kept Kagami, if he was so protective of kids. Either way he'd warned them of a raid by an allied clan and judging by the fact that nobody had returned with news yet, it had been a real warning. Just one of the healers dragging in Torino half dead and chilled from hiding in the river without a shirt. 

The Hagoromo had betrayed them. Fucking great. Izuna had faith in his brother's skill, but he wished he could be out there with the defense. Instead he was stuck here babysitting an overloaded sensor former-fish maybe-yokai and his little cousin. 

By the time everyone returned, with no casualties thankfully, Shirochi had dozed off and was sleeping fitfully. Kagami kept cooing at him until he stopped twitching in his sleep. It was ridiculously adorable. 

Shirochi woke up with a start when Madara entered the healing hall. A few clansmen were injured, but nothing serious. 

He sat up, eyeing them all warily. 

“It appears,” Madara said with a quirk of his lips. “That I owe you another debt for the lives of my kin.” 

Shirochi shook his head. “No debt is owed. You- I was merely… you took care of me, this winter. I wanted to- I couldn't just not do…” He was very, very obviously overwhelmed still. And suddenly very anxious about several people watching him at once. 

Izuna wondered if he really talked to anyone, before this past winter. His awkwardness in conversation had been slowly getting better the more they talked by his pond. But he was back to shrinking in on himself, now. Maybe even worse than before. 

No, definitely worse than before, because Kagami was looking up at him with a lot of worry in his eyes. 

Madara considered the pathetic looking man deeply. “If you are willing, I'd like to speak to you later on extending our previous offer.” 

Izuna perked up. His friend needed people to drag him out of the water and talk a bit. If Madara wanted to offer him the chance to live there fulltime, Izuna wouldn't protest.

Tobirama left the Uchiha compound mid May with a busy mind and an offer to return the next winter to shelter in his pond and every year after. His pond, officially. 

Somehow he'd ended up an official ally to the Uchiha. Tobirama thought that Butsuma might be rolling in his grave. 

The thought made him ridiculously happy as he pushed upriver through rushing waters.