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After defeating Shigaraki at Jakku things went back to normal for a while, or as normal as things got for Midoriya Izuku. Most of the boy’s time and energy were spent on recovering and later, pushing his limits with One for All. And sleeping, a lot of sleeping. Izuku deserved it after he and his classmates—his friends—were thrust into a war many of the adults didn’t come home from.
Considering what they’d gone through, it was no surprise that his sleep wasn’t as restful as he’d like. Even when he didn’t remember his nightmares, he knew he must have had them with how tired he woke up some mornings. At least he had the 1-A group chat for those nights he couldn’t shut his eyes without seeing death and dust. There was always someone online, and it reminded him he wasn’t alone in his struggles.
Starting their second year at UA was a much-needed return to routine. He was back under the same roof as all his friends, and he felt like he could breathe again. His mother had hovered so much after Jakku, constantly checking if he felt alright, saying he should get some more sunlight—he was looking more pale than usual—pestering him to eat more. Even katsudon turned his stomach half the time now, and he couldn’t find the words to tell his mother why. Some days he wasn’t even sure himself.
When the problem stretched from days into weeks, Izuku contemplated scheduling an appointment with Hound Dog. Then one morning he woke to a painful stomach ache and all his joints throbbing like a storm was about to break. He laughed to himself and hobbled to Recovery Girl’s office instead. This whole time he was coming down with something, and his immune system finally gave out. That explained everything. (It explained nothing.)
The antibiotics and pain medication helped, and he focused back on his training. Since the start of the spring semester, he’d been stuck at 45% with One for All, and he couldn’t seem to push past it, no matter that he trained til he was short of breath and beyond. It was frustrating. He’d taken down Shigaraki, but he couldn’t master his own quirk. Looking around at his classmates, it felt like he was falling behind all over again.
So, he pushed himself, and he pushed some more, even while his gut was slowly recovering from whatever he’d caught. But instead of improving as the semester wore on, Izuku found himself flagging. 45% hurt all of a sudden, and he couldn’t maintain it. Danger Sense jolted through him, and he dropped his hold on One for All as if burned. It left him shaky and breathless, blinking to rid his vision of dark spots while Danger Sense died down to a faint buzz that didn’t completely go away.
He wasn’t sure when his friends stopped their own practice to gather around him, but when something tapped his shoulder, he looked up from where he was hunched over with his hands on his knees to see Jiro looking down at him. There was more concern on her face than he’d ever seen from her before. “Hey, you should rest. Your heartbeat’s off.”
Izuku blinked up at her, wondering what she meant. Then he paid attention and felt it. His heart was beating fast—too fast—and uneven. Izuku must have taken too long to respond to Jiro, because she turned away to yell across the gym, “Aizawa-sensei, something’s wrong with Midoriya’s heart.”
Izuku stood up straight once more, and his vision blurred slightly. A large hand steadied him, and he looked up to see Shoji beside him. Shoji nodded to their teacher when he sprinted over to them, as fast as ever despite the prosthetic leg. “He’s been getting short of breath a lot the last few days too, maybe longer.”
Aizawa scanned Izuku with his one eye before taking the boy’s wrist to check his pulse. He frowned almost immediately and turned to the gathered students. “Iida, rush Problem Child to Recovery Girl. Don’t let him walk.” The teacher turned his dark, searching gaze back to Izuku as he added, “You shouldn’t strain yourself with an arrythmia. I’ll call ahead to let her know you’re on your way.”
Izuku didn’t quite get what everyone was so worried about. He was breathing fine now, though tired. He’d pushed himself a little too hard. Nothing out of the norm. He was sure his heart rate would even out once he took a break.
But even Recovery Girl seemed concerned when she saw Iida carry him in. She whispered something to Iida and shooed him from the infirmary before running through Izuku’s usual exam. She hesitated when she shone a light in his eyes. She squinted at something there a moment longer then frowned. “I’m going to run some blood tests.”
“Okay,” Izuku said absently. Maybe he could take a nap while waiting for the results. He couldn’t seem to get enough sleep these days. His eye bags were going to rival Shinso’s soon at this rate. After Recovery Girl had the blood she needed, Izuku lay down on the uncomfortable infirmary bed and let his eyes fall closed.
All Might shook him awake what felt like seconds later. “Young Midoriya, you need to get up. I’m driving you to the hospital.”
“What?” Izuku croaked, barely awake. He rubbed at his eyes and turned a confused look from All Might to Recovery Girl. He was still so tired. Why were they going to the hospital? He just needed more sleep.
“Midoriya, you need a hospital. Something’s wrong with your liver, and your blood isn’t carrying enough oxygen. Your heart rhythm hasn’t returned to normal either.”
The words she spoke sank into his brain like molasses and eventually made sense. “W-what? What’s wrong with me?”
A familiar bony hand squeezed his shoulder. “We’re going to find out. It’ll be alright, my boy.”
As soon as they walked into the ER, the staff swarmed them, apparently having been alerted prior to their arrival. They had no intention of keeping the former Number One Hero and his protégé waiting. Izuku was urged onto another hospital bed, and he was carted off for more tests and blood draws.
Finally, the nurses and doctors left him in a room hooked up to an IV drip and heart monitor. The machinery hummed and beeped away in the silence while a nasal cannula provided him a steady stream of oxygen. At least All Might was sitting in the chair beside the bed now; he hadn’t been allowed back in the radiology department.
Izuku let out a shaky breath. The reality of the situation was beginning to set in. It didn’t escape either of them that Izuku’s room was in the ICU. All Might took his successor’s trembling hand and held it gently as they settled in to wait. “It’s okay, Young Midoriya. I am here.”
Izuku drifted off at some point and woke to see a nurse checking his IV, which was hooked up to way more things than he remembered. There was a second line running into his other arm too. That one was running a blood transfusion, and the first one had smaller bags of medication feeding into his original fluid drip.
The nurse smiled at him when she saw he was awake. “Evening, Midoriya. You can get some more rest if you want. They won’t be by for your bone marrow biopsy until your transfusion and your first bags of iron chelators and ampicillin finish.”
“What?” Was that sentence even Japanese? Maybe Izuku wasn’t completely awake yet, though he did feel more present than he had in…a while. He frowned. How long had he been feeling bad?
The nurse blinked in surprise at him before she seemed to realize something. “You’ve been asleep for a few hours. I’ll fetch the doctor and your teacher to go over everything with you.” True to her word, a doctor and one of his teachers stepped in a minute later, though this time it was Aizawa instead of All Might.
“Problem Child,” Aizawa greeted. His tone was a bit softer than when he was teaching. Normally, it was comforting, but right now it only made Izuku worry more.
How bad was it? Why did he need another transfusion? He’d had two after Jakku, and they’d cleared him then. Had those doctors missed something? A hand on his head stilled his runaway thoughts, and he glanced up to see Aizawa raising an eyebrow at him.
Seeing he had the kid’s attention, Aizawa nodded to the doctor, who started talking. Izuku had iron overload, because his body wasn’t using it to make the hemoglobin (the protein that carried oxygen in his blood) he needed. So, the iron built up in his blood and organs instead. It had recently reached toxic levels and was damaging his liver, pancreas, and heart. They had no idea why his body had suddenly stopped making half the hemoglobin it should, but based on the rate of change to his bloodwork since his hospital stay after Jakku, it had to have started in the last year and a half. They suspected he’d been hit by a quirk at some point that caused it.
As Aizawa sat beside his bed, the hero poured over villain profiles, looking for a culprit. Izuku recognized some of the faces from the USJ attack. Wow, that felt like ages ago. Did something back then really cause this? He didn’t know, but he hoped everyone else was okay. Tsu and Mineta had been with him almost the entire time at the USJ.
Izuku must have started muttering at some point, because Aizawa answered his worry without looking up from his files. “Everyone in 1-A is getting checked out, Problem Child. If any of them are similarly affected, they’re not as far along as you. They’ll be okay. Worry about yourself for a change.”
Aizawa did have a point. No one else had been having trouble keeping up in class, at least not that Izuku had noticed. Maybe that meant it was a villain only Izuku had run into? Izuku wracked his brain for what villain encounters he’d had in the last year and a half. Wait…Izuku blinked. He was thinking about this wrong. Not only villains had used their quirks on him. He shuddered as he thought of his old middle school.
He swallowed at the sudden dryness in his throat and picked at his sheets. “A-Aizawa?”
His teacher paused and looked up at him, though Izuku didn’t meet his eye. “Yes, Problem Child?”
“If…If none of the villains at the USJ match, and everyone else in class is fine…you might want to check my middle school.”
Izuku felt something in the air of the room shift, and he scrunched his shoulders up around his ears. He barely kept himself from flinching when Aizawa spoke next. “Midoriya, are you saying…”
Izuku nodded and tried to offer a reassuring grin, but it died before it fully formed. “My quirk came in very, very late. No one in middle school knew about it.”
Aizawa didn’t seem like he wanted to leave things there, but Izuku was saved from having to play 20 Questions by a knock at the door. A nurse informed them it was time for Izuku’s bone marrow biopsy.
All thoughts of middle school evaporated before thoughts of how big a needle they must need to bore through bone. Thankfully, he never had to find out, as they knocked him out for that part. He could definitely feel where they’d taken their sample from when he woke up though. Why did it have to be his hip? Now he couldn’t get even the slightest bit comfortable on the damn hospital bed.
At least his mom was there when the sedatives wore off. She fretted and fussed, but Izuku knew that was only because she loved him. They talked and shared a small meal of the blandest food Izuku had ever tasted before she had to leave for work, and only then did Izuku realize he must have been in the hospital overnight.
He slept some more, waking up when a nurse changed out one of the small bags connected to his IV line and took his vitals. She left him what must have been a lunch, but Izuku’s stomach rebelled at the sight and smell of it. He yawned and rolled over to face away from the “food.” Maybe he’d feel up to eating later. It wasn’t like he needed the energy with him lying in bed all day, and he was just so tired. He ignored the persistent buzz of Danger Sense and drifted back to exhausted slumber.
He didn’t remember having a hypoglycemic seizure a few hours later.
---
All for One was many things: brilliant, cunning, powerful, even maliciously patient when it suited him. He did not often feel fear or dread. In fact, he could count the number of instances he had felt it in the last century on one hand, and all but one of those had been due to his family. This time was unfortunately no exception, though it had snuck on gradually rather than racing through his veins like a hound after a hare.
He had his usual routine at Tartarus down to a T. Wake up, eat the paltry breakfast that was offered, sit through the prison staff’s medical and security check, contemplate unconventional uses of at least five of his less used quirks, run through Search’s rolodex of tagged people, etc. Then there were the few tags he kept permanently active to amuse himself or stay informed throughout the day. That was how he’d known when the battle at Jakku broke, how he knew Izuku took down the Shimura pawn, how he knew Izuku never quite returned to 100% afterward.
He wrote it off as the boy’s recovery, but after a few weeks, All for One noted a steady increase in health problems pinging Search. Fatigue, anemia, thinning and brittle bones, and a slew of symptoms that sounded eerily reminiscent of iron overload. All for One stilled at the thought. No, no, it couldn’t be that. Izuku had made it through his toddler years without issue; he was in the clear. Or he should have been.
The symptoms only worsened over the following days and weeks, and All for One rationalized all the similarities away. It wasn’t that. He’d had Garaki run the genetic tests to make certain of it. He only had one copy of the faulty gene. It couldn’t be that.
All for One swore loudly when Izuku had a seizure because his blood sugar dropped too low. The boy’s pancreas was damaged! Did those imbeciles honestly think his body was capable of regulating its insulin and sugar levels correctly? As the panicked guards around All for One’s cell retreated before his tirade and killing intent, the intercom warned him to calm down or be sedated. The supervillain barely heard them, his thoughts elsewhere.
He couldn’t ignore this anymore. He’d walked this road before, remembered too many of the sign posts. He would not stand by and watch his family waste away. Not again. Not to this. How Izuku had it, All for One couldn’t fathom. The genetic disorder should be a non-issue. The only way the recessive mutation could manifest was if something had interfered with Izuku’s genetics…
All for One growled under his breath. Of course, if was that cursed quirk. Since its creation, every problem in his life always came back around to it. The whole point of One for All was altering its holder’s genetics, blending it with those who’d held it prior and strengthening the current holder. That’s why it had saved his brother. The quirk’s original holder had clean genetics, and All for One had been very careful to keep the quirk isolated from his own while he held it. He was unfortunate enough to carry one faulty marker, and it would have defeated the purpose of his gift if he’d replaced one of his brother’s bad genes with his own.
So many times, he should have ended that quirk, but it slipped through his fingers each encounter. And then All Might had the audacity to give the quirk All for One created to All for One’s son. And now the quirk was killing that son.
This was not going to do at all.
If those incompetent doctors weren’t going to take proper care of the boy, then All for One would do so himself, regardless of what plans he had to scrap in the process. He’d already had to drop a few when Izuku managed to defeat Tomura, and those plans were much longer in the making. It was a pity though. Another week, and the Commission’s president would have visited for her annual evaluation of the prison. Oh well, there would be other opportunities. There wouldn’t be another Izuku.
Breaking out of Tartarus was laughably easy. Breaking into the hospital was even less of a challenge. Irritatingly, it seemed there was one competent person who had his son’s best interests at heart, and that one person was Eraserhead. That wouldn’t have been a problem, except that he was guarding Izuku when All for One entered his son’s hospital room to retrieve him.
Erasure truly was a marvelous quirk. All for One could have done without experiencing it himself. Having one’s longevity quirk erased was very unpleasant. The only reason he still drew breath was that the hero had blinked in shock when the most powerful supervillain in Japan collapsed in a heap at his feet.
All for One warped out of there the second the hero blinked and did not intend to face Eraserhead again. Not out of embarrassment! Purely because he valued his continued existence.
Well, he’d lost the element of surprise now, but that just meant he’d have to exercise a bit of subtlety. And investigate a few leads. While the information All for One could glean from Search was limited, he was very good at extrapolating, and he had observed something very interesting around six months ago.
Izuku being Izuku had injured himself quite awfully with One for All. Again. This was disappointing, but not unexpected. What grabbed All for One’s attention was how the damage simply vanished a split second later. And then it happened again. And again. After the seventh or eighth time Izuku maimed himself and instantaneously healed, All for One caught what was actually happening. The injuries were being rewound as soon as they were inflicted. And if too long passed between injuries, the rest of Izuku started to rewind.
It was incredibly curious, and no small amount maddening. All for One still intended to have words with Izuku about that at some point. The pattern of purposeful self-injury had long since grown disturbing.
But, the rewinding quirk…that was useful in All for One’s current situation. He spent several hours using a quirk that allowed him to mentally interface with technology to research what events happened six months ago, finally stumbling across a video taken by a reporter. The footage was of an aerial battle that took place during a raid on the Shie Hassaikai. The glow of One for All unfettered was unmistakable, though there was another glow—a golden, sparkling one—intertwined with it.
He made a mental note to pay Overhaul a visit in Tartarus after he was done here, then focused on the video as his son brought Overhaul back to ground, landing shortly after. Ah, there was the rewinder. A little girl clung to Izuku’s back. A good look at the little one, and All for One was able to tag her with Search.
UA offered no better deterrent to his presence than Tartarus, and he was lucky enough to find the child alone in her room. The two studied each other for a few silent moments. All for One broke the stillness first by kneeling on the rug before her. “Hello there. You’re a friend of Izuku’s, correct?”
The girl, who had curled in on herself the longer she spent in his presence, perked up at that. “Deku?”
All for One suppressed a sigh at his son’s idiotic choice of a hero name. Honestly, who willingly takes a quirkist slur that’s been used against them for a decade as their professional, hero name? It would have made sense for a villain, perhaps, but All for One honestly could not see Izuku’s reasoning here. At least, it was better than Mighty Boy or All Might Jr.
“Yes, Eri. I’m here because of Deku.”
The girl wilted just as quickly as she’d perked up, hugging a stuffed unicorn to her chest. “Deku’s sick.”
“Yes, he’s very ill, but I want to help him. To do that I need your help.”
Eri tilted her head in confusion, and All for One for a moment wondered what it would have been like if he and Inko had had that second child she wanted, a daughter. (Would she have had the same hauntingly familiar green eyes, the same sunlight smile, the same dauntless idealism as All for One’s little brother and Izuku?)
“You see, little one, I have a quirk that can help Izuku, but I was badly hurt a few years ago.” All for One lifted his mask just enough for Eri to catch a glimpse of his scarred face. When her eyes widened, he clicked his mask back into place. “Since then, I haven’t been able to use my quirk very effectively. Do you think you could help me?”
Eri stared at his mask for a few seconds, then ran one of her small hands up and down her covered arm. She bit her lip and looked back up at All for One. “I’m not supposed to use my quirk without Zawa. So, I don’t…h-hurt someone by accident,” she said so softly All for One almost activated a hearing quirk out of habit. “But I want to help Deku!”
All for One hummed. “Smart, but Eraserhead isn’t the only one who can stop quirks. I can stop them too. You won’t hurt me.” He slowly held a hand out to Eri, stopping several inches short.
Eri seemed uncertain for a minute but slowly inched closer. “Promise?”
“I promise.”
Rewinding was understandably painful, but All for One had been through worse with less promise of reward. He thanked Eri as he shed his respirator and helmet for the first time in years. Eri stared in wonder, clearly seeing the family resemblance to Izuku in his new-old face. Oh, it was good to see with physical eyes again. He gave Eri a smile and conspiratorial wink. “Thank you, Eri. You did wonderfully.” He’d forgotten what his voice sounded like without all the damage and the intrusive tubing. He smiled wider. “As a thank you, do you want me to get rid of your scars?” he asked, pointing toward the sleeved arm she had rubbed at earlier.
“You can do that?”
“Mhm. Izuku has been getting into trouble long before he was a hero. Until I was injured, I took away his scars.” When he could. Sometimes it was too risky to return home, especially once All Might started tracking down his assets. In retrospect, perhaps preventing his young son from facing permanent consequences for his injuries had contributed to his present disregard for his person. All for One frowned slightly at that thought.
Thankfully, Eri didn’t notice. She was too busy thinking and worrying her lip—which All for One was half sure was a habit learned from Izuku. Finally, she looked back up at him. “No thank you.”
All for One blinked down at her, frowning.
“Deku said scars aren’t bad. They show you’re strong.”
All for One couldn’t help the grin tugging at his lips. “Did he now? He is pretty smart, isn’t he?”
When Eri nodded her agreement, Hisashi leaned over to tap her on the head with one finger, pulling on a quirk he hadn’t had need of since Tomura was little and prone to temper tantrums. She fell asleep in an instant, and All for One caught her as she fell. He carefully wiped the last 20 minutes from her memory before settling her in a pile of stuffed animals.
He couldn’t have anyone knowing he had his face back, now could he?
That taken care of, Midoriya Hisashi set out to secure his cover story. And call Inko. He couldn’t just show up in Japan without preamble if he wanted to keep his alias and insides intact.
He hit one of his oldest safehouses for a change of clothes and a burner phone. Then he took the elevator down to the broken vault. He hadn’t been here since…He shook his head. The air here was stale and choked with dust, and everything was as he and his brother had left it. More a mausoleum than the living quarters it was intended to be.
He coughed and stepped past the cracked and dark-stained sections of concrete by the hanging door, moving to a closet in the back of the room. The hinges on this door screamed with rust and remembered arguments. Hisashi pointedly ignored the threadbare ghosts of clothing hanging there, instead reaching for the box on the top shelf.
It was heavier than he remembered. Hefting the box with barely any assistance from his strength quirks, he left that place of bitter failure and broken promises. Once he was aboveground again, he dialed Inko’s number from memory and set the box on an empty table to sort through.
Inko’s voice was a balm to the anxiety Hisashi hadn’t even realized was eating away at him. The fact she was chewing him out for his unexplained missed check-ins these last nine months made him smile. There was that steel he’d fallen in love with. Quirks, he had missed her. For the thousandth time, he cursed All Might for making him leave her and Izuku.
He placated Inko and explained himself in enough half-truths and apologies to earn her grudging tolerance, though he suspected he’d be sleeping on the sofa for a while yet. That was fine. There would be time to get back in his wife’s good graces after he saved their son.
---
It was a reasonable and altogether agonizing day and a half (to account for travel time from America as per his cover story) later before Hisashi appeared at the hospital with a smaller and newer box in his hands, an overnight bag over his shoulder, and several additional quirks floating in his chest.
While retrieving said quirks from one of Garaki’s old bolt holes, he watched Izuku stabilize but barely improve via Search. The doctors weren’t treating the root cause. How could they when they were looking at a genetic disorder no one had seen since the Dawn of Quirks? So many life-threatening disorders died out of the population in Japan during the Quirk War when medical care and supplies were limited. So much knowledge and so many medical and technological advancements were abandoned for “more pressing” issues.
Well, it was a good thing Hisashi had kept his own copy of all research he could find pertaining to his brother’s condition alongside a copy of his brother’s medical file. Everything he brought was carefully edited to exclude incriminating information.
He checked in at the front desk, then made his way to the ICU. He decided to corner his son’s doctor first, sensing that a certain rail-thin retired imbecile was present in his son’s room and wishing to put off the inevitable encounter. He dropped the box on the counter of the nurses’ station and grinned in that way that always let his subordinates know they were on thin ice. “Is Dr. Murano in?”
One of the suddenly pale nurses nodded and typed something on her computer, presumably to summon said doctor. Hisashi waited, resisting the urge to drum his fingers on the counter. As much as he loved inflicting a healthy sense of fear in people who’ve objectively failed to do their jobs, he needed them still able to think clearly enough to use the information he’d brought. So, he took a deep breath and reeled in the bit of his murderous aura that had slipped out.
“Someone was asking for me?” a man in a lab coat asked as he approached the station.
Hisashi offered the man a slightly tamer smile than he’d given the nurses and offered him a hand to shake. “Midoriya Hisashi.” The doctor took his hand, and Hisashi noted the man’s fever-reduction quirk. Useful, but not exceptionally unique. Some part of him was disappointed. “I heard from Inko about what happened and flew back as soon as I could. I think I know what’s causing this,” he said, taking his hand back to rest it on the box.
The doctor’s eyebrows rose. “You know whose quirk is causing the reaction?”
Hisashi blinked at the man. Was that what they were thinking? Honestly, did they assume a quirk was responsible for every odd medical phenomenon? Hisashi wondered if genetic disorders were actually just as common as before, only misdiagnosed. “No. It’s hereditary. His un—great great uncle had the exact same thing. Apparently, my great grandfather had 1 copy of the bad gene responsible too. So, he made sure to warn all his descendants what symptoms to watch for, just in case. After this many generations though, I’d thought the family line had gotten free of it.”
With that, Dr. Murano led him to his office to sift through the medical papers and charts Hisashi had brought. Izuku’s faceless illness finally had a name: thalassemia major. Names were said to be things of power, and Hisashi believed that, to an extent. Now that Izuku’s doctor had the name of their foe, he also had the weapon with which to end it. (There were really two weapons, but only Hisashi had access to the second. And he’d prefer not using it unless he could arrange for Garaki to be present to doublecheck his work. That man had always had an affinity for genetic manipulation.)
“According to this, the only real cure is a bone marrow transplant,” the doctor murmured, studying a rather dry research paper as if it were the Mona Lisa. “Finding a suitable donor will be difficult though…That procedure’s only been done a handful of times at this hospital during my tenure. Since the advent of quirks, most peoples’ biology is just too varied to be compatible with another’s.”
“Check mine.”
“Hm?” Dr. Murano looked up from the paper, as if only now recalling the guest in his office.
“I’m his father. If anyone’s going to be a close enough match it’ll be me or Inko, and I’d rather you check me first before presenting the option to her. Let me do this.” The last was not a request.
The doctor assessed Hisashi for a solid minute before nodding. “Alright. I’ll get you the forms to fill out. Do you want a clipboard so you can work on them while visiting your son? A nurse will be waking him up soon for a meal if he isn’t up already.”
Hisashi remembered his brother picking at his food but never eating more than a few bites before pushing his bowl away. Superimposing Izuku on that memory nearly made him grimace. “Yes, I’ll do that.” Even if he had to put up with the blonde beacon of idiocy. Izuku and his health were more important.
Hisashi repeated that to himself over and over as he walked back down the hospital hallway. He reached Izuku’s room, showed his id to the police officer on guard detail, and knocked on the door before opening it, already knowing both occupants were awake.
Hisashi paused in the doorway to let Izuku and All Might stare at him with slightly different shades of incredulity. He, in turn, studied them. All Might seemed just a touch unnerved, which made Hisashi all the prouder of keeping his “civilian” and villain lives—and appearances—separate. And as for Izuku…Hisashi’s little boy had gotten so big. He hadn’t had a chance to really appreciate how Izuku’d grown after his injury and self-imposed exile. His son looked like he might be taller than Inko now, and Hisashi was for a moment torn as to which shade of green was his favorite. Then Hisashi started cataloging everything else. Izuku’s pallor, the bruise-dark bags under his eyes, the faint grey tint to his skin, the scars. Now that he could see Izuku directly, all the constant aches and pains in the boy’s arms registered. He could also sense the presence of his brother’s quirk pulsing in his son’s veins like the countdown of a bomb.
Izuku broke the standoff first. “Dad?”
Hisashi grinned warmly. “Izuku.”
All Might looked between the two in confusion. What? Could he not see the family resemblance? “Young Midoriya, I thought you said your father was ‘working overseas.’”
“I was,” Hisashi said, walking to stand at the side of Izuku’s bed not occupied by All Might. “When I talked to Inko and heard what happened, I threatened the boss into letting me return. I have more than enough paid leave stored up. I’ll be here as long as you need me, little spark.” He gently ruffled Izuku’s hair.
Izuku blushed at the pet name from back when he was convinced he’d manifest a fire quirk. He mumbled something about all parents being embarrassing.
Whatever he’d said made All Might chuckle. “I’ll let you two catch up. I should check in with the doctors before I head back to campus anyway.” The shadow of the Symbol of Peace made for the door. Hisashi noted with amusement that he kept glancing over his shoulder as if sensing danger, but unable to ascertain its source or form.
Hisashi couldn’t help himself. He gave All Might a wolfish smile right before the door closed, cutting off his view of the hero’s startled expression. Perhaps not the wisest thing he’d done in his 214 years, but considering the Eighth wasn’t bleeding out on the floor at this moment, Hisashi thought he’d shown remarkable restraint.
Hisashi was pulled from his admittedly petty satisfaction by Izuku’s next words. “Sorry for pulling you away from work, Dad. I can’t imagine how expensive booking a flight last minute must have been.” The boy’s eyes were resolutely set on the blanket over his legs. He sounded genuinely guilty.
“None of that, Izuku. I wish I’d been able to get here sooner. You are worth far more than any airfare or perceived inconvenience. There are billions of yen in the world but only one you. Money can be replaced; you cannot.” Hisashi let his son think on that while he pulled up a chair. He settled in and started working through the packet of papers Dr. Murano had given him.
Before the silence could become awkward a nurse arrived with Izuku’s lunch. Hisashi caught the face Izuku made at the offered food before schooling his features into a polite mask. His son picked the bowl of miso soup off the tray to show he was a good patient, though he stared down at his bowl of soup long after the nurse left.
Hisashi waited another few minutes before reaching over to card his hand through Izuku’s hair. If he activated a quirk or two to suppress his son’s mounting nausea and the pain associated with it, no one needed to know. “You need to eat, Izuku. Please try?”
Izuku offered him a wan smile. “Mom told you about my seizure, huh?”
“Yes, but even if she didn’t, I’d want you to eat.” Hisashi wondered if Izuku had already built an association between eating and feeling worse and if that was why he was so resistant to the idea. Countering a psychological effect like that was tricky. Perhaps a distraction was in order to prevent his intelligent son from overthinking. “I’ll tell you a story while you eat?”
That sparked some interest in those emerald eyes. After Izuku nodded, Hisashi leaned back in his chair and debated which story to tell and how edited it needed to be. Finally, he settled on one that needed hardly any revision at all. “I met Inko 19 years ago in the middle of a mugging.” Hisashi let that teaser hang in the air until Izuku caught on and raised a tentative spoonful of soup to his lips. “Some druggie was holding up a teenage girl and threatening her with his elongated metal fingernails. Did you know your mother’s quirk works on any small object? Even if it’s attached to something bigger?”
Hisashi smiled one of his less-than-nice smiles at the light of realization in his son’s eyes. Hisashi nodded approval. “Yes, she nearly ripped that fool’s fingernails out. Then she hit him in the face with her purse while the girl ran away. To this day I don’t know what she had in there, but it took the man down in one hit.” Hisashi laughed. “I witnessed the whole thing from the other side of the street. I couldn’t take my eyes off her. After the mugger hit the ground, she kept him pinned under one of her high heels until the police sirens started to get close. Then I punched the guy out for her and told her she should probably get going. I couldn’t let such a stunning creature get arrested for vigilantism, now could I?”
“We ran into each other again a few weeks later, passing the same alleyway on opposite sides of the street again.” Hisashi left out how he’d never walked that way before the incident but walked it every day after hoping to see the woman who’d entranced him again. “Both of us just kinda froze and stared at each other. Then Inko pointed over her shoulder to a coffee shop on her side of the street and turned around to walk inside. I met her there a few minutes later. We talked over drinks and traded numbers just in case she ever needed me to punch someone again.” Hisashi grinned at the face Izuku made at that.
“We didn’t properly start dating for another month or two, though we did meet up for coffee a few more times. Once while we were there, a purse snatcher ran by with a hero in pursuit, and Inko tugged on one of the criminal’s shoes to trip him. To this day she denies having anything to do with it, but I called her my Little Vigilante for the better part of a year after that.” If only for the way she blushed and looked away to hide her smile at the nickname.
A wadded-up napkin hit the side of Hisashi’s head, and he blinked in surprise. He turned an incredulous stare on Izuku. Izuku made a rather poor attempt at not laughing. “I don’t need to know your pet names for Mom. I’m not going to be able to get that out of my head now,” he said with mostly fake dismay.
“Mhm. I’m sure that’s the worst you’ve ever heard. You know, with some of the things she’s told me, I think I can see where you get your recklessness from.”
Izuku stammered denials and shakily waved his hands in front of him. Izuku nearly knocked over his bowl with his antics, but Hisashi caught it before anything could spill. He smiled when he saw there was less than a spoonful left in it. Mission accomplished.
---
After Hisashi turned in his paperwork, it was a few hours before Dr. Murano got back to him and scheduled his bone marrow biopsy. If he was a match for Izuku, they’d schedule another procedure for collecting a larger sample. Whilst whiling away the time, Hisashi had the misfortune of meeting several of Izuku’s teachers and friends. All seemed a touch skeptical of him—or outright hostile in the case of one Bakugo Katsuki—but largely ignored him in favor of attending Izuku.
Then there was the visit from Inko. When Hisashi sensed her enter the hospital via Search, he left Izuku—who had fallen asleep shortly after his friends’ visit—to meet Inko where any shouting might not wake the boy. His expectation wasn’t for nothing, as Inko stormed up to him in the hallway and slapped him. The kiss immediately after was a nice surprise though.
“Don’t you ever disappear like that again! Do you have any idea how worried Izuku and I were? We were starting to think we’d lost you.” Inko had tears in her eyes, though the anger was still there.
Hisashi hesitantly pulled her into a hug, giving her plenty of time to escape if she wished. He whispered apologies that were much more heartfelt than his excuses over the phone. He wasn’t sure how he was going to handle “returning to work” after Izuku’s recovery. But…now that All Might was out of the picture, maybe he didn’t have to stay away this time. Supervillains were allowed to take vacations, right?
They talked a little longer as they meandered back to Izuku’s room. Eraserhead was on guard/guest duty now, camped out in the chair All Might had used earlier, his obnoxiously bright sleeping bag rolled up under the seat. The hero glared Hisashi down until Inko introduced him. Then he relaxed as much as any underground hero ever did, which was not a lot. Since there were only the two chairs inside the room, and Izuku was still sleeping, Hisashi retrieved his overnight bag and excused himself, ostensibly to make a call for work. In truth, he was cutting it close for the check-in for his procedure.
The front desk directed him to an empty room, and he didn’t have long to wait before Dr. Murano and the nurses came for him. The worst thing about the whole affair was having to deactivate all of his defensive and regeneration quirks for the process. He felt uncharacteristically antsy with only Search and Longevity active. Waking up after, he breathed a sigh of relief as his favored quirks all came rushing back and the pain in his hip rapidly faded. A few more hours of observation, and he was free to go.
Hisashi returned to Izuku’s room with a set of kamaboko udon dishes from a restaurant down the street. He even picked one up for the teacher he grudgingly respected, if only to prevent Izuku from trying to give up his own bowl. Hisashi texted Inko on his way back, explaining how he’d gotten Izuku to eat earlier. This time Inko took up the duty of storytelling while everyone ate. Izuku struggled with the first bite or two of fish, but he seemed fine after that.
Hisashi wasn’t the only one watching Izuku, and he caught Eraserhead’s eye partway through a story of how Inko and Mitsuki almost got arrested for “disturbing the peace” back in college. The hero’s dark eye flitted down to Hisashi’s hands then back to his face. Hisashi looked down and nearly choked on his mouthful of noodles when he realized he’d forgotten to take off his hospital id bracelet. He hurriedly shoved it back under his sleeve, glad that he’d worn one of his dress shirts today. Eraserhead’s arched eyebrow told Hisashi the hero wasn’t going to simply forget the slip. So, Hisashi pointed at his bowl then glanced toward the door. They’d talk after eating.
And once Izuku finished most of his bowl, they did. Eraserhead slipped out first. Hisashi exited a minute later, ruffling Izuku’s hair and reapplying the nausea suppression quirk. That was probably the heaviest meal his son had eaten in a while; the last thing he needed was to lose it. “I’ll be right back.” Hisashi took the meal’s trash with him as he left the hospital room. The hero leaned against the wall near the door, waiting for him. Hisashi indicated down the hall with a nod, and the two set off.
When they reached the waiting area and its large trashcan, Eraserhead stated, “You didn’t have that when you left earlier.”
“No, I didn’t.” Hisashi quickly snapped the incriminating hospital band and tossed it in the trash. “They’re checking my bone marrow for compatibility. Izuku needs a transplant. I didn’t want to get their hopes up until we know if it’s even possible.”
The hero nodded. “How soon will they know?”
“A few days. If we’re a match, they’ll take a bigger sample and start Izuku’s conditioning.” Hisashi grimaced when he remembered the protocol that his brother had been too sickly to undertake. Radiation or chemotherapy had to kill off the faulty cells in Izuku’s bone marrow before the new, healthy ones could be introduced. That was going to be far from fun for Izuku, but it was the only way to save him.
---
They were a match.
Dr. Murano told Hisashi, Inko, and Izuku together and went over the treatment plan. Izuku seemed most nervous about the whole putting a giant IV catheter in his chest bit. Hisashi couldn’t say he blamed his son. They were going to have him awake for the procedure, and they were essentially stabbing him in the chest.
Hisashi did what he could with his quirks and reassurances to make the situation easier for his boy, but his gut still twisted uncomfortably as they took Izuku to the OR to place the central line. Then it was his turn again. They used his other hip this time, assuming there’d still be inflammation at the first site, and Hisashi was grateful he didn’t have to come up with an excuse for why that hip was already healed.
After that more painful procedure and while Hisashi was still alone, he decided there were only so many chances he was willing to take. With Izuku’s scared-but-attempting-to-be-brave face stuck in his mind, he snuck into the hospital’s lab and took one vial from Izuku’s most recent bloodwork set. After the thalassemia major was settled, he didn’t want any more potentially fatal surprises for his son.
A quick teleport to one of his and Garaki’s labs that the heroes never discovered gave Hisashi all the equipment he needed. Turning it all back on and running the proper updates, calibrations, and blanks was a pain though. A few hours later saw a full genome sequencing in progress and several other specialized tests running in parallel. Now that that was taken care of, Hisashi had his family to get back to.
The following two weeks passed in a miserable blur, both for Izuku and those keeping him company as the chemo did its job and made Izuku feel worse and worse. Then one last anticlimactic injection of Hisashi’s donated stem cells through Izuku’s central line, and the transplant was done. The hospital planned to keep Izuku for a few more days to keep an eye on him and monitor his bloodwork and immune suppressant dosage to ensure the transplant took.
Hisashi wondered if Izuku should be on quirk suppressants too. The chance was small, but with how One for All and its holders all seemed hellbent on killing him, there was the smallest chance the quirk might react negatively to the new stem cells that bore All for One’s DNA. He hadn’t considered the possibility initially, but with some of the truly bizarre results his lab had turned up, Hisashi wasn’t putting it past the ancient and possibly sentient quirk. (There was also the even smaller chance that the DNA in those donated cells might become incorporated into One for All, but he’d worry about that bridge if they had to cross it.) So, he watched Izuku and One for All like a hawk in the days following the transplant, rarely leaving his side.
Thankfully, the only odd occurrence was One for All activating on its own on the third night. The sudden green lightning nearly gave Hisashi a heart attack, but Search didn’t turn up anything detrimental going on. Of course, the damn quirk deactivated itself by the time a nurse rushed in to see what was wrong. He was pretty sure the nurse thought he’d hallucinated it. When Izuku woke up the next morning, he’d only looked at Hisashi oddly and said he’d had a weird dream. He refused to elaborate or talk much at all that day.
Interestingly, Eraserhead seemed to be the only one to believe him (of those he mentioned it to). And All Might, though Izuku was the one to tell that menace when he thought no one else was in earshot. Hisashi paused outside the room before deciding to wait to enter. The policeman on guard duty gave him a questioning eyebrow raise, but Hisashi merely grinned as he settled against the wall on the other side of the door. “Kid’s talking to his prede-mentor. I’ll wait until they’re done.” Hisashi pulled on a hearing enhancement quirk that wouldn’t affect his external appearance and focused on the room behind him, tuning out the rest of the noise around him.
“What did they want to show you this time?” All Might asked.
“A few of them wanted to warn me about something,” Izuku started, sounding far too serious for a teenager. “But First wasn’t worried. He seemed more…happy? Maybe closer to bittersweet. I’ve only seen him impassive or angry before. And the anger was only in his memories with All for One.”
Externally, Hisashi maintained a calm façade. Internally, he was reeling from the implication that a piece of his brother was alive and aware inside One for All even two centuries later. What monstrosity of a quirk had he created?
“Oh? What was it they wanted to warn you about?” All Might asked.
“All for One. Who else? but I’m pretty sure none of the predecessors have a quirk that could let them monitor whatever All for One’s doing right now. So, I don’t see what there is to worry about. T-though I’m not 100% sure what Second’s q-quirk is.”
Hisashi heard the bedding rustle, and he frowned. Stammering and picking at his sheets were two of Izuku’s tells. Why was his son lying though? And what about?
All Might hummed. “That is odd. Aside from that one attempt to reach you here in the hospital, no one’s seen hide nor hair of him since his escape from Tartarus.”
“Do you think Eraserhead killed him?”
“I hesitate to say yes. After all, look at what happened when I thought I had killed him.” All Might chuckled softly. “Are you sure this wasn’t another quirk coming in? You had a dream before Black Whip, and it’s been a while since you got Float and Danger Sense.”
What.
“Ugh. I hope not. I don’t know if I can handle something else manifesting right now. Danger Sense is giving me a headache with how constantly it’s been active ever since being admitted. I wish it came with an off switch.”
“I wish there was more I could do to help. Just know that whatever happens, my boy, I’ll be here for you.”
“Thanks, All Might.”
Hisashi let out a breath. Yes, All Might was always there for Izuku…after pushing Hisashi out of the picture. He was wishing now that he’d never left. It would have spared his son this at least and being in the League’s line of fire. He hadn’t even known Izuku had gotten into a hero course until Tomura reported back from the USJ. By then it was too late to intervene.
Hisashi mentally shook himself. What was that old saying? Don’t listen to conversations you weren’t meant to hear unless you want to hear things you don’t want to know? Hisashi tuned his son and nemesis out and let his hearing quirk slot back into place in his chest, turning his attention to parsing the information he’d just gained. One for All kept at least pieces of the holders within it and apparently their quirks as well. And those other quirks were manifesting inside Izuku? None of the previous holders exhibited that. Is it because Izuku was quirkless? But then why didn’t it happen with All Might? Did it hit Singularity? Hisashi straightened at that thought. He needed to double check something with Izuku’s labwork.
---
Izuku was being released tomorrow at long last. He still had to pop back by the hospital every couple days for blood tests and the occasional transfusion, and he was still on immune suppressants for the next week and iron chelators for another two months as a precaution, but he was going back to UA where the various hero teachers could guard him and Recovery Girl could monitor his progress.
If Hisashi was going to do this, tonight was his only chance.
He waited until the other visitors had left, the nurse rotations had slowed down, and he knew he had a few hours before Eraserhead was due to stop by following his patrol. Hisashi ran a hand through Izuku’s hair and confirmed that his son was soundly asleep. Then he pulled on one of his healing quirks. He settled his hand on the crown of Izuku’s head and activated it. It was an old one, it required a lot of concentration on the specific repairs needed, only worked for damage that wasn’t externally visible (for some reason tissue exposure to sunlight messed things up), and it was not terribly energy efficient for the user, but All for One had long since collected enough energy storage quirks to compensate. The main draw with this one was its ability to affect old injuries such as the damage to Izuku’s internal organs from the iron overload—damage that he was very familiar with. Whatever he could do for Izuku’s arms was a bonus. The scars were going to stay, but everything internal should have been taken care of.
Hisashi felt drained by the end of it, but he was satisfied with the relatively short list of lingering problems showing up in Search. Most of those would go away as the new stem cells took root and started producing healthy red blood cells. He lifted his day bag over his shoulder and stepped around the bed to reach the small table Izuku’d left his notebook on. One of his friends brought it for him, and Hisashi had already looked through its frankly astounding analyses. Granted, he’d had to use three of his intelligence quirks at once to decipher the code it was written in, but that just showed that Izuku knew the value of his knowledge.
Hisashi pulled a folded piece of paper from his pocket and placed it in the notebook where Izuku had left off writing. His son didn’t need his physical presence anymore, as much as it pained him to admit (and only then in the solitude of his own mind). His little spark had others he relied on now. There was no place for a father long overdue. Hopefully, Izuku would read the note and email he’d sent and believe the test results.
“Dad?”
Hisashi froze beside the table. “Yes, Izuku?”
“You’re leaving.” There was something resigned in his voice and eyes.
Hisashi sighed. Was he a coward for having hoped he could leave without Izuku waking up? Those eyes were a bigger weapon than One for All. “Yes. I have a flight to catch, and…you’re in good hands.” He meant Inko and Eraserhead, obviously. That blonde buffoon was the one who allowed his son to hurt himself with One for All for so long. He wasn’t worthy of caring for a hamster, let alone Izuku. But Izuku was fond of him. So, All for One had decided to be patient and let the man suffer and die slowly without his interference. If he enjoyed the other’s suffering vicariously through Search, that was his own business.
“How long this time?”
The lack of emotion as Izuku asked stung more than Hisashi cared to admit. “I don’t intend to disappear again, Izuku. I will call weekly and video chat when I’m able. I’ll work out the timing with Inko for whenever you’re home, but I won’t come back in person unless you want me to.”
“And…if a hero smashes in your face again?”
Hisashi stiffened slightly. “You know?”
Izuku nodded and turned his head away from Hisashi. “Since the dream I had. You look different now, but One for All recognized you, your quirk, your DNA. Did you know that when you try to take someone’s quirk, you temporarily leave DNA traces behind even if you didn’t take it?”
Hisashi stared dumbly at his son. Huh, he’d analyzed plenty of people, but he’d never had it turned on him before. Like father, like son, he supposed. He fought back a smile and cleared his throat. Right, he had best get back on topic so he could make a clean getaway before Eraserhead arrived. “You don’t have to worry about me trying with you.”
Izuku didn’t look at him but shrugged. “I figured.” Then he frowned and rolled his shoulders, then opened and closed his hands several times. He finally turned back to face Hisashi. “Did you do something?”
Hisashi gave a small smile. “I healed what I could. The scars will stay though.” They ran too deep for the quirk he’d used during Izuku’s childhood.
Izuku huffed what might have been a small laugh. “That reminds me, First wanted me to say congratulations for finally kicking thalassemia major’s ass, even if it wasn’t for him.”
Hisashi puffed up slightly in mock offense. “I’ll have you known I did beat it the first time too…but Ichiki had been so sick for so long that a transplant was out of the question. And by the time I found the right quirk…”
After a few beats of silence, Izuku asked, “Ichiki?”
Hisashi grinned fondly. “The kanji mean ‘precious one.’ Even as a baby he was sickly. Our mother refused to name him until he was out of the NICU for fear that he wasn’t going to live. When he pulled through, he became her instant favorite. To be fair, he was my favorite too.”
“Why give him a quirk when he didn’t want it though? How was that supposed to help?”
“Same reason as you presented with thalassemia major now instead of when you were one year old. Quirks affect genetics, little spark. And One for All, stripped of its stockpile, was small and gentle enough to introduce that it didn’t kill Ichiki in the process. It knocked out one of his bad gene copies. You can live without symptoms, if you only have one. When you inherited One for All, it still carried traces of Ichiki’s—and every other holder’s—DNA. You got a bad copy of the β-hemoglobin gene from your uncle, giving you two copies. You already had one from me. And now that One for All likely has two copies of that bad gene, this” Hisashi waved his hand to the surrounding hospital room. “is very likely to happen to anyone you feel inclined to give the quirk to in the future, if the transfer doesn’t kill them outright.”
“Wh-what? What do you mean? Why would it kill someone?”
“Quirk gene overload, and it’ll likely be a very quick death now that One for All’s hit Singularity and is giving you the others’ quirks. You’re handling it fine, because you had no preexisting quirk gene for One for All to force its way into. The space for your quirk gene was empty, so to speak. Those with quirks…there’s not enough room for a second quirk, let alone seven. I saw it to a lesser extent when I was first experimenting with my quirk. The tests I ran with the blood sample I took—from the lab!—showed pieces of the previous holders' DNA when I ran it through a sequencer. Every last one of those strands shows genetic damage or decay…except yours and All Might’s.”
“We’re the only two who were quirkless,” Izuku said, staring off into space for a moment before looking back at Hisashi with distrust shining in his eyes. “H-how do I know you’re telling the truth?”
Izuku no doubt hoped this was a hoax, a ploy to prevent him from continuing the line of One for All. Hisashi almost wished it was. The way the quirk was now, it was very likely to kill even him. He was never going to hold that last piece of his brother. But…it did seem oddly fitting that Izuku held it, now that he was no longer in immediate danger from it.
“You don’t, but I emailed you all the test results I got. I know how much you love quirks. I’ll let you draw your own conclusions from the raw data." Hisashi paused a moment before continuing with his voice a little softer, "And I know how much you care for others. You would be destroyed if giving your quirk to someone led to their death. Believe it or not, I do care for you. As my son, not as the Ninth holder of my brother’s quirk.”
“You seem to have trouble showing it,” Izuku grumbled.
Hisashi frowned and averted his gaze. “Yes. I’ve never been the best at that, but I do love you, Izuku. I’ve learned a bit from Inko, but I’m a slow learner, it seems. My brother may have hated me for doing what I did, but I did everything in my power to save his life…and yours. Would you do anything less for someone you love?”
After a few minutes passed, Hisashi took Izuku’s silence as a dismissal. He sighed and was gone.
---
Izuku had been watching the supervillain out of the corner of his eye the whole time, but he turned at the last moment to see the afterimage of Hisashi fade out of existence. “Love you too, Dad…” he said barely above a whisper.
He replayed that conversation dozens of times in his head as he lay there, poking at his father’s words and his strangely pain-free hands from every angle. If there was a lie in that exchange, he couldn’t spot it. He’d have to ask First’s opinion next time he found himself within One for All. Until then, All for One’s last words in particular stuck with him. The determination, the surety that he’d do whatever it took to keep those he loved safe…that was the same determination he saw in the mirror every day he went on patrol during his work studies, every time he suited up for a mission, in the locker room before his Sports Festival match with Todoroki.
All Might and his friends often teased him for his devotion to saving others. He was…very different from his mother in that regard. She was great! But…she never did anything to save him from his bullies or their bruises and burns. He’d had to suffer through or save himself. It was more unsettling than he’d thought it would be to realize he’d gotten that stubborn resolve to save from his dad.