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After their usual morning run, Jaehyun and Sungchan parked themselves on a bench at the edge of the park. The air still smelled like wet grass and sweat. Jaehyun was halfway through a long swig from his sports bottle when he caught Sungchan staring at him again. Not subtle. Not even trying.
“Okay, man,” Jaehyun said, lowering the bottle. “Out with it.”
“Out with what?” Sungchan replied, lips twitching like he was holding back a laugh.
“You’ve been looking at me weird all morning. What’s going on?”
“Seriously?” Sungchan wiped his forehead with the back of his hand. “Sion didn’t tell you?”
“Tell me what?” Jaehyun asked, brow knitting.
Sungchan leaned closer, voice dropping even though no one was around. “Dude. Your brother and my brother are doing the thing tonight.”
Jaehyun blinked. “The… thing?”
Sungchan nodded, fast and proud. “That thing.”
Jaehyun stared at him. “Like—that, IT?”
Another nod. Bigger this time.
“Bro,” Jaehyun said slowly. “Like first base to home plate?”
“All of it,” Sungchan grinned. “Yushi’s freaking out, by the way. First time and all.” He laughed under his breath. “He even made me buy condoms. Just in case Sion doesn’t have any.”
Jaehyun’s mind short-circuited. A thousand thoughts collided at once, most of them unhelpful. Sungchan reeled him back to earth with a crooked smile.
“I got a large,” Sungchan added. “Or is he rocking XL like you?”
Jaehyun didn’t answer. He didn’t know, and somehow that wasn’t the part bothering him. All he could think about was Sion. Nervous. Overthinking.
As Sion’s hyung, this was his job. Make sure his younger brother didn’t walk into this blind. Make sure he was okay. Confident. Prepared. Came out on top. Literally, if possible.
“Thanks for telling me.”
“No problem,” Sungchan replied. They bumped fists like always.
“I should head out,” Jaehyun said, already standing. “Check on Sion.”
“Same time tomorrow?” Sungchan called as Jaehyun jogged off.
“Yeah,” Jaehyun shouted back, jogging backward for a second. They waved, then split off.
Inside the car, Sungchan’s words kept looping in Jaehyun’s head. Tonight. In a few hours, his precious brother would become a man. Jaehyun had taught Sion everything growing up - how to balance on a bike, how to hold chords without buzzing strings, how to study smarter instead of harder. Even how to flirt. No surprise Sion turned into a campus heartthrob, just like Jaehyun had been. Still was, if he was honest.
So yeah, it shocked him when Sion came out a couple years back. But the adjustment was fast. Sion was still Sion. Labels didn’t change that.
What "did" change things was the secret Jaehyun never said out loud.
●
His calves protested as he climbed the stairs, each step a dull reminder of the ten kilometers. Of course, the elevator was busted. "Ugh. Today, out of all days. Just my luck," He exhaled through his nose and kept moving. With every floor, his thoughts circled back to the same question:
How the hell do you prep your brother for something like this without being weird?
He reached their door, digging for his keys, when he heard it. - A sound. Soft. Rhythmic. Familiar.
Jaehyun stopped in his tracks.
It was coming from inside.
He unlocked the door discreetly, easing it open just enough to slip in. The noises are palpable now.
What is he doing?
He moved on instinct, stepping carefully. Quiet as a mouse. When he reached the corner of the hallway, he peeked out—
And there was Sion - bare.
On the living room carpet. The fuzzy one, they always argued about vacuuming. Sion was on his knees, hands gripping the silicone hips of a realistic male toy—just the lower half—thrusting into it with messy urgency. All elbows and eagerness. No rhythm. No grace. Like he’d watched enough but never really learned.
Jaehyun almost laughed. But didn't. Couldn't.
It was painfully obvious this wasn’t something Sion was used to, not like this. Jaehyun knew his brother masturbated plenty. But this—this was a different ball game.
And then something shifted.
Jaehyun’s focus narrowed. The curve of Sion’s spine. The way sweat droplets cling to his back. The flex in his thighs. The muted, breathy sounds slipping out of him. Sunlight spilled through the window, painting Sion in gold, exaggerating every sharp line of his lean frame.
It hit harder because Sion resembled him. Too much like him. People said it all the time. They could pass for twins - sexy, hot twins.
Most people would shut that thought down instantly.
Jaehyun didn’t.
The feeling bloomed, immoral, curling deep in his chest. Protecting. Teaching. Guiding. Wanting.
His breath caught when he realized how hard he was. His shorts pitched high, fabric pulling tight. Like his dick could tear through it. It was ridiculous. But it was there. Sion did this to him like no one else ever had. Seeing him like this - open, nervous, trying so hard - sent heat straight through him.
He felt sweat gather at his temples as he quietly set his bag down. Clothes came off. He spat into his palm, wrapped his hand around himself, and shuddered at how ready he was.
Then Sion’s movements faltered. Followed by frustration.
Jaehyun didn’t think anymore.
His brother needed him.
So, he stepped out from the hallway, walked over, and grabbed Sion’s waist.
Sion froze. Gasped. Twisted around, eyes wide, breath punched out of him when he saw who it was.
Jaehyun leaned close, mouth near his ear, and whispered:
“You’re doing it wrong.”
●
“H-Hyung—” Sion stutters, unbelieving that:
a.) Jaehyun caught him in the middle of his little shenanigans, and that-
b.) his older brother was kneeling right behind him, completely naked.
“It’s okay. It’s okay,” Jaehyun murmurs, calm. “Let me teach you.”
His palm slides over Sion’s shoulders, grounding. Sion’s breathing evens out, the panic dissolving as realization settles in. Jaehyun isn’t here to scold him. He never has been. He’s here the same way he’s always been. For him.
That same hand snakes down, unhurried, slithering around Sion’s lean waist, tracing over the ridges of his eight-pack, before closing firmly around the base of Sion’s cock. A grip that isn’t rushed. Lustful, yes, but also evaluative. Like Jaehyun is weighing him, measuring him.
“First,” Jaehyun states, “ensure your partner is prepped.”
He pulls his hand away just long enough to spit into his palm, then brings it back, stroking Sion with purpose. Each word lands with a matching glide of his hand.
“You lick his hole. Rim him."
Stroke.
"Fuck him with your tongue.”
Stroke.
“Finger him.”
Stroke.
“Until he’s loose enough.”
Sion hums faintly at every instruction, barely registering the lesson over how Jaehyun’s rough palm drags against his sensitive skin, how the friction gives him goosebumps.
“Second,” Jaehyun continues, spitting into his hand again, layering slick over slick, “you prep yourself.”
His cadence stays maddeningly slow as he strokes Sion again, milking him this time.
“You make sure this big dick of yours is nice and wet.”
Another glide.
“Especially if you’re fucking him raw.”
Sion lets out a low moan, eyes falling shut, his head tipping back onto Jaehyun’s shoulder. That gives Jaehyun a perfect view.
He takes it in. Sion’s cock, long and throbbing in his grasp, already drooling, thick drops of precum sliding down his fingers and pooling at the base. Jaehyun’s mouth actually waters. He knows what he’s working with, knows his own size, and even so - Sion is packing. Comparable. An impressive 8 1/2 inches.
Sion’s breath turns deeper, heavier. He starts rocking into Jaehyun’s hand in slow arcs, chasing the pressure. Each movement makes Jaehyun’s own hard length brush against the cleft of Sion’s ass, a constant reminder of what’s behind him.
“And when you’re wet enough,” Jaehyun instructs, “you stick it in him. Slow.”
Sion opens his eyes just in time to watch Jaehyun guide the tip of his cock, circling it around the toy’s opening, smearing it with slick.
“You had trouble fucking it before, I suppose. Too much friction, yeah?”
Sion drones, hazy, cock-drunk already, hardly processing how obscene it feels to be talked through this.
“You make him beg,” Jaehyun adds. “Beg for your cock. You get that?”
“Y-Yes. Yes, hyung—ah,” Sion rasps.
“And when he sounds like he’ll die without it,” Jaehyun whirrs, lining Sion up properly now, “you slide it in.”
He does it for him. Painfully slow. The toy stretches as Sion’s tip presses in, breaches, sinks. Sion moans louder, the pleasure more perceptive with Jaehyun controlling the pace, his cock already slick enough to glide instead of burn.
“See?" Jaehyun traces the tip of his nose along Sion's neck. Sending shivers down the younger's spine. "Feels better.”
It does. He was right. Of course he was.
“Make him feel it,” Jaehyun continues, never saying Yushi’s name, never letting Sion realize he knows. “Every inch of your big, veiny dick.”
Each emphasized word matches another inch fed into the toy.
“Give him time,” Jaehyun's free hand roams Sion’s chest, brushing over his nipples before pinching them just hard enough to make Sion gasp. “He'll need it."
Sion’s moans climb as Jaehyun keeps pushing him deeper.
“Listen to him. Feel him. And if you’re unsure—ask.”
He leans closer, lips near Sion’s ear.
“‘Are you ready for this, dick?’”
“Fuckk,” Sion groans. Jaehyun’s voice alone is wrecking him.
“Once he says yes,” Jaehyun goes on, hand sliding down to Sion’s hips, “you fuck him. But slow. Show him you’re in control.”
He moves Sion for him, rocking his hips back and forth at a glacial pace. Slow enough that they can hear the toy squelch.
“Man… this feels so good,” Sion pants.
“And I’m sure he’s feeling amazing too,” Jaehyun taunts. “Imagine taking a dick so big you feel it in your guts.”
Right then, Sion notices the shape of his cock bulging through the toy, hadn’t even realized he was fully buried. The sight in itself steels something in him.
“So you ask again,” Jaehyun coos, “‘You want this?’”
A pause.
“‘Want me to put a baby in you?’”
Sion makes a needy sound and echoes him without thinking. “You want this? Want this dick to knock you up?”
“That's right. And when he says yes,” Jaehyun stresses, “you fuck him stupid. You hear me? You fuck him good.”
“F-Fuck—yeah,” Sion whimpers as the pace finally picks up. His hips whip faster, reckless now, the cleft of his ass rubbing against Jaehyun’s harder, thicker cock.
“That’s it,” Jaehyun growls. “Fuck him like it’s the last time. Make him remember. Let your cock mold his insides.”
He spits into his hand and slicks his own shaft, observing intently.
“Oh my God, hyung—this feels insane,” Sion howls.
Behind him, Jaehyun smiles, something wicked stirring as he watches Sion’s perky ass cheeks close around the upward curve of his spit-greased, red cock, soaking it further with every grind.
“So,” Jaehyun asks smoothly, “you wanna feel even better?”
“Yes—yes,” Sion blurts, needy, wrecked, already knowing.
“Then beg,” Jaehyun purrs.
“Please—please—” Sion half moans, half sobs. “Please give it to me.”
“Give you what?” Jaehyun feigns innocence, rubbing his tip against Sion’s hole again and again, letting it catch, letting him feel it.
“Y-Your dick,” Sion keens. Feeling Jaehyun's precum douse his tailbone. “I need Hyung's horse cock in my pussy.”
And there goes his last string of control.
Hearing Sion—his lil' brother, the school heartthrob, ripped and gorgeous—beg like that makes Jaehyun twice as hard, feral with want.
“You want it?” Jaehyun growls. “Then take it!”
He pushes Sion forward, bending him slightly, lines himself up, and eases in, slow enough to watch Sion shake when the blunt tip breaks inside.
Sion cries, tears spilling as more of Jaehyun’s thick length stretches him open, raking his walls.
“God—your dick’s so huge~ shitt,” Sion sobs, feeling every heavy vein. He knew he was big. But Jaehyun is - Longer. Thicker. Ruinous.
The sensation snaps something in him.
He doesn’t wait. He doesn’t ask.
Needing more, needing the burn, Sion throws his ass back and starts fucking himself on Jaehyun’s cock with no permission.
“Fuck—” Jaehyun snarls. “You n-nasty little slut.”
He watches, transfixed, as Sion rides him harder, wetter with every slam. A quarter turns into half, then more, taking him at a pace that makes Jaehyun’s head spin. Sion’s mind has melted into nothing but need, a singular hunger to be fucked and filled.
He was addicted to his hyung's superior dick. As pain was gradually morphing into a high he has never felt.
Jaehyun drops to the balls of his heels, bracing himself, abdomen tight, glistening under the sunlight, staring at the lewd picture of his hot brother riding his cock while still fucking the toy, butt cheeks clapping as he takes both.
Sion is completely gone now, drooling, screaming nonsense.
“I’m close—fuck~ I’m so close,” he wails.
●
Then, like a strike of lightning, Sion barely had time to gasp before Jaehyun’s strong arms hooked beneath his thighs and lifted him clean off the ground. They went down together in one fluid motion, bodies hitting the carpet with a soft thud that knocked the breath out of him. Sion ended up on top, Jaehyun still buried deep inside, which only made Sion cry out harder, his cock still lodged inside the toy.
“Do it,” Jaehyun growls into his ear. “Show hyung how much you can cum.” His teeth graze skin as he mutters - “Show me how much you love getting wrecked in the arse… and fucking someone’s dirty hole.”
Jaehyun’s hands slide from behind Sion’s thighs up to the toy, his feet planting firmly against the carpet for leverage. Sion’s eyes go wide as Jaehyun suddenly starts slamming the toy up and down his length. Fast. Brutal. He watches helplessly as his cock gets drenched in its own slick, red, and swollen beyond anything. He’s so close, so painfully edged, right on the brink—
And then Jaehyun snaps his hips upward.
Hard.
Over and over, pelvis lashing skyward with abandon, fucking his little brother's hairless, rosy pucker so fast it almost blurs. Sion breaks completely, sobbing and screaming Jaehyun’s name like a prayer, voice cracking as he loses himself. He isn’t a person anymore. He’s a thing. A toy. Something made purely for his hyung’s ruined pleasure.
What finally pushes him over is the sight of his own lower stomach. He looks down and freezes.
There. Clear as day. The unmistakable shape of his brother’s cock jutting out beneath his skin.
~He’s the toy now.
“Hyung—hyung—hyunggg!!” Sion yells, and then his body locks up and detonates into the toy like a geyser. His whole frame jerks violently, orgasm ripping through him so hard it feels spiritual, like his soul is also coming undone. Both of them watch thick blobs of cum ooze out of the toy and splatter across Sion’s groin every time Jaehyun yanks it down again. The wet sounds, the visuals, it’s pure porn.
Sion is spiraling, overstimulated, and shaking, unable to move when he feels Jaehyun’s horse cock swell even more inside him. Bigger. Thicker. Demanding more space.
So he begs.
“Breed me, hyung,” Sion gasps, broken. “Breed your brother's cunt. Please—I need you, please!”
And who is Jaehyun to say no?
He’s wanted this longer than he’d ever admit.
“If I knew you were this much of a size queen,” Jaehyun groans into his ear, “I would’ve ruined you a long fuckin' time ago.”
With a deep, guttural moan, his muscles flex, balls pulling tight as his cock grows impossibly thick. Then he empties himself, dumping a preposterous load straight into the younger man’s innards.
Sion feels every second of it.
Warm jets flood him from the inside, filling him completely as Jaehyun keens and thrusts through it, riding out the release. His cock comes out and torpedoes back in, drenched in froth and cream, spooge spilling down to his heavy balls as they sway with each movement.
Their moans echo through the golden-lit space, racy and breathless. Jaehyun feels Sion’s hole clamp down again and again, still fluttering at the peak of his orgasm, just as Sion tosses the toy aside and starts fisting his still-hard cock with frantic desperation.
“Yes—yes~ keep fucking that spot, hyung,” Sion screams, high and needy. “Keep fucking me. Make me cum—make me cum again!”
Jaehyun doesn’t hesitate. He grabs behind Sion’s knees and rolls him effortlessly onto his side without pulling out, guiding him until Sion’s flat against the carpet. In one smooth motion, Jaehyun lunges forward, folding him in half, one knee planted, the other stretched back, noses brushing as he unleashes hell and obliterates Sion’s guts.
Sion screams, pumping his cum-soiled meat wildly, pleasure tearing through him.
Their eyes lock.
Jaehyun crashes his mouth against Sion’s, kissing him rough and hungry, then pulls back just long enough to watch how obscene his cock looks plunging in and out of his brother's clinging rim before kissing him again, messier, deeper. They break apart on a strangled moan from Sion, both of them staring down as Jaehyun rearranges him completely.
Past their flexed abs, Sion’s flushed cockhead spurts rope after rope of white, painting both their torsos. Cum drips into the grooves of their sculpted midsections, sliding between muscles, making an absolute mess of them. There’s so much of it that Jaehyun feels himself throb again, becoming so aroused past overstimulation.
“Holy shittt,” Jaehyun whimpers, pupils blown wide. “G-gonna cum. G-gonna fuckin' nut—”
Seconds before he does, Sion suddenly shoves him back. Jaehyun lands on his ass, legs spread, just in time for Sion to dive between them and take his cock into his mouth.
The image alone nearly kills him.
Sion worships him shamelessly, sucking down a quarter of Jaehyun’s massive length, hands twisting the rest he can’t fit. Even with just that much, he’s gagging nonstop, throat working desperately.
There’s no stopping it now.
Sion looks up, eyes locked with Jaehyun’s, begging silently for it.
Jaehyun snarls and fists the back of Sion’s hair, gripping so tight it stings his scalp, and fucks straight into his eager, constricting throat until he breaks.
GAWK.
URKK.
URGHK.
He expects less this time.
He’s wrong.
His cock bucks violently in Sion’s mouth, spraying almost a dozen viscous jets straight down his throat. Sion swallows greedily, lapping at every pulse, making a mess of himself as Jaehyun spasms in pure rapture. Cords of white spill from his slit, streaking across Sion’s face, hair, and neck, pearlescent and filthy. It's enough to make Jaehyun think he could come all over again.
Sion finally slows, smiling softly as he licks Jaehyun’s cum-slicked cock, from its base to the frenulum, even slapping it against his tongue several times before murmuring, “Thanks for showing me how it’s done.”
Jaehyun smiles back, handsome and spent, cupping Sion’s face, smearing his cum across his skin.
That smile drops when Sion smirks and requests—
“How about you teach me and Yushi again tonight?”
Fuck.
⏹