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The apartment they share is small, cheap, and on the third floor of a building that smells faintly of fried food and old tatami. It’s the kind of place a twenty-year-old part-time sidekick and a fifteen-year-old UA hopeful can afford when their dad has made it clear that rent money is not forthcoming. One bedroom, one bath, a living room that doubles as Denki’s room, and walls so thin that every breath in the night carries.
It starts slow, after that first mortifying almost-moment on the couch. They swear it won’t happen again. They swear a lot of things.
They start policing space like it’s a battlefield.
Akeru stops draping a wing over Denki’s shoulders when they watch movies. Denki stops reaching for the downy feathers at the base of Akeru’s wings when he passes behind the couch. They keep a cushion of air between them on the train, in the kitchen, on the bed they still share when Denki has nightmares about middle-school bullies or the entrance exam or the way Dad looked at him the last time they spoke.
But his instincts, their bond spurred on by said instincts, they don’t care about sworn oaths. It hums under Akeru’s skin like a second heartbeat, reminding him every minute that his chosen person is hurting, or anxious, or just existing three meters away when he should be closer. And Denki, sweet oblivious Denki, still smells like home to him: ozone and citrus shampoo and the faint crackle of uncontrolled electricity when he’s nervous.
So they orbit.
It’s a Wednesday night in mid April, two weeks before UA opens. The city is humid, the AC is broken, and Denki had already locked himself in the bathroom for forty-five minutes after dinner because he walked in on Akeru toweling his hair, wings half-spread to dry, water beading on black-and-gold flight feathers like liquid starlight. Denki had frozen, mouth open, brain short-circuiting so hard his quirk actually sparked off his fingertips and scorched the doorframe. Akeru had laughed, awkward and too loud, and said something about personal space. Denki had bolted.
Now it’s past midnight. Akeru is restless, pacing the narrow hallway in nothing but loose sweatpants, wings folded tight against his back because if he lets them loosen he’ll start preening again and that way lies madness. He can hear Denki through the wall. Not loud. Just the soft, helpless sounds of a teenager who discovered internet porn at twelve and has exactly zero chill about it.
Akeru knows he should go to bed. He knows he should put headphones in. He knows the walls are thin and that this is the third time this week.
Instead he finds himself standing outside Denki’s door, one hand raised like he’s going to knock, except he doesn’t. The door is cracked two inches, spilling a blade of gold from the desk lamp. Denki is on his back on the bed, sheet kicked to the side, one arm flung over his eyes, the other moving in slow, guilty strokes beneath the waistband of his boxers. His breathing is ragged. Every exhale carries the faintest whine, like a puppy dreaming.
Akeru’s wings flare before he can stop them, primaries brushing both walls of the hallway. The sound is soft, but unmistakable: feathers on plaster. Denki freezes.
The silence stretches, thick and electric.
Then Denki’s voice, hoarse and cracking: “. . . Bro? You need something?”
Akeru’s mouth is desert-dry. His field is buzzing, unstable, little arcs of gold-white static licking over his collarbones and the inside of his wrists. He can taste Denki’s charge in the air, sweet and metallic, like licking a battery. His brother, his bondmate, is hurting with want and trying so hard not to be loud about it and every instinct Akeru has is screaming to fix it, to press close, to drag his lips along that frantic pulse in Denki’s throat and promise it’s okay, I’ve got you, let me take care of you the way I always have.
He pushes the door open another inch with one knuckle.
Denki is propped up on his elbows now, flushed from collarbones to ears, eyes wide and glassy. The sheet is clutched in one fist like a lifeline, doing absolutely nothing to hide the obvious. He looks wrecked and young and like he’s been crying a little, maybe from frustration, maybe from shame.
Akeru’s voice comes out rougher than he means it to. “Walls are thin, ototo.”
Denki makes this broken little sound, half laugh, half sob. “I-I know, I’m sorry, I tried to be quiet-”
“You weren’t.” Akeru steps inside. The door clicks shut behind him. “I heard you the last three times, too.”
Denki’s face crumples. He curls forward, knees to chest, trying to make himself small. “I’m gross, I know, I’ll stop, I’ll-”
“You’re not gross.” The words rip out of Akeru before he can stop them. He crosses the room in two strides and drops to his knees beside the bed, wings half-spread for balance. “You’re fifteen. You’re supposed to be horny. It’s normal."
Denki peeks at him through the fringe of his hair, eyes wet. “You’re not supposed to hear it.”
“I’m not supposed to want to come in here and-” Akeru cuts himself off, jaw clenched so hard it aches. His quirk is flickering, jumping between them like a live wire. He can feel Denki’s charge answering it, little helpless sparks dancing across his bare forearms, a natural consequence of sharing space.
Denki’s voice is barely a whisper. “And what?”
Akeru’s hands are shaking. He reaches out, slow enough that Denki can pull away, and cups the side of his little brother’s face. Thumb brushing the hinge of his jaw, right where the scent glands would be if Denki had any. “And fix it for you,” he says, the confession dragged out of him like a tooth. “Like I fix everything else.”
Denki’s breath hitches. His eyes flick to Akeru’s mouth, then away, then back again. “That’s. . . not what brothers do.”
“No,” Akeru agrees, voice raw. “It’s not.”
The silence is huge.
Then Denki leans forward, just a fraction, pressing his cheek into Akeru’s palm like he’s done a thousand times since he was four. Except this time his lips part on a shaky exhale and the sound that comes out is a soft, desperate please.
Akeru breaks.
He surges forward, wings flaring wide to cage them both in shadow and gold, and kisses his little brother like a man drowning. It’s not gentle. It’s months of restraint snapping all at once: teeth and tongue and the low, possessive growl he’s never let Denki hear before. Denki whimpers into it, hands fisting in Akeru’s hair, legs falling open without thinking. Static arcs between them, bright and painless, lighting up the dark like a storm.
When they pull apart, panting, Denki’s pupils are blown wide, lips swollen, a thin line of saliva still connecting them.
“We’re so fucked,” Denki whispers, half-laughing, half-crying.
“Yeah,” Akeru says against his mouth, wings already curling forward to wrap them both up tight. “We really, really are.”
The room turns into nothing but heat and breath and the low, constant crackle of their quirks brushing against each other like live wires. Akeru’s wings have curved forward until the primaries brush the edges on either side of the bed, a living canopy of black and gold that blocks out the lamp and turns the world into something small and safe and theirs. Denki is trembling beneath him, thighs spread wide, knees hooked over Akeru’s hips like he’s afraid his brother will vanish if he lets go.
Akeru is gentle. He is so, so gentle it hurts.
He remembers being thirteen and shaking apart in the dark, remembers the first time Denki’s small, curious fingers had slipped between his flight feathers and stroked the velvet-soft down at the base of his wings. Remembers the way his entire body had locked up, the way his wings had flared so violently the primaries knocked over a lamp. Remembers their father’s voice, low and furious: It’s inappropriate, it’s impolite, and it’s not something brothers do, Akeru. Remembers the way his father’s own wings had been mantled in rage, the way he’d grabbed Akeru by the scruff of his neck and shaken him until his teeth rattled. Remembers crying into his pillow afterward while his body betrayed him in ways he didn’t have words for yet.
He remembers thinking, even then, that if he could just be gentle enough, careful enough, good enough, maybe it would stop feeling wrong.
So now he is gentle the way drowning men are gentle with the last piece of driftwood.
He kisses Denki’s mouth until it’s soft and open and gasping. He kisses the hinge of his jaw, the frantic rabbit-pulse under the skin, the hollow beneath his ear that still smells faintly of the citrus, quirk-safe shampoo they’ve shared since Denki was nine. He drags his lips down the column of Denki’s throat and feels the boy’s electricity answer him in helpless, stuttering waves that make his own field flicker gold-white in response.
Denki is shaking under him, small, helpless sounds punched out of his throat every time Akeru’s mouth moves lower. Akeru is being so careful it hurts. Careful the way he always wanted to be when he was thirteen and locked in his bedroom with his face buried in a pillow that still smelled like Denki’s shampoo from the night before, humping the mattress until his wings cramped and tears soaked the fabric because he was disgusting, he was broken, he was wrong.
He isn’t thirteen anymore.
“Shh,” he whispers against the hollow of Denki’s throat, voice ragged. “I’ve got you. I’ve always got you, Denks, I’m sorry, I’m so sorry-”
He isn’t sure what he’s apologizing for anymore. For wanting this. For waiting this long. For the way his static field is curling around them both like a living thing, drinking in Denki’s electricity and giving it back softer, warmer, safer. Their quirks have always fit together like puzzle pieces; Denki’s wild, spitting voltage sliding harmless into Akeru’s field, grounding out harmlessly, leaving only heat behind.
He kisses Denki’s collarbone like an apology. Like a prayer. Like the first time he ever defibrillated someone and felt a heart stutter back to life under his palms. Gentle. Reverent. Terrified.
Denki makes a broken sound and arches up, fingers scrabbling at Akeru’s shoulders, at the leading edge of his wings, anywhere he can reach. His nails catch on the delicate skin where wing meets back and Akeru shudders so hard his elbows nearly give out. His hands are in his feathers again, trembling fingers carding through the down at the base of his wings, and Akeru makes a sound that is half-sob, half-growl. His hips jerk forward involuntarily, grinding against Denki’s thigh, and Denki arches up with a broken little cry that goes straight to Akeru’s spine.
He pulls back just far enough to look.
Denki is flushed and wrecked and beautiful, eyes glassy, lips bitten swollen. There are tear tracks on his temples, disappearing into his hairline. He looks fifteen in a way that makes Akeru’s chest cave in with guilt and want in equal measure.
He mouths down Denki’s chest, slow, worshipful, tasting salt and ozone and the faint sweetness of teenage skin. He circles one nipple with his tongue and feels Denki jerk beneath him, a sharp cry punched out of his throat. Static arcs between them, bright and painless, dancing over Akeru’s tongue and making Denki sob with overstimulation.
When he reaches the waistband of Denki’s boxers he pauses, forehead pressed to the boy’s stomach, wings trembling with the effort of holding himself still.
“Tell me to stop,” Akeru says, voice cracking on every syllable. “Tell me no, tell me right now and I’ll stop. I swear on everything, ototo, I’ll-”
Denki’s answer is to thread both hands into Akeru’s hair and pull him down.
Akeru goes willingly.
He mouths over the cotton, slow and wet, until the fabric is soaked through and clinging. Denki is babbling now, incoherent little pleas and broken repetitions of nii-san, nii-san, please, need you. Akeru hooks his fingers in the waistband and drags the boxers down, freeing Denki’s cock to slap against his stomach, flushed dark and leaking at the tip.
“Akeru-nii,” Denki whimpers, hips rolling helplessly. “Please.”
That name in that voice is a blade straight through whatever’s left of Akeru’s conscience, and he makes a sound like he’s dying.
He doesn’t tease. He can’t. He swallows Denki down in one slow, deliberate slide until his nose is buried in soft blond curls and Denki is crying, back bowing off the mattress, hands fisted so tight in Akeru’s hair it has to hurt. Akeru doesn’t care. He hums, low and possessive, and the vibration makes Denki’s thighs clamp around his head like a vice.
He works him with tongue and lips and the faintest graze of teeth until Denki is sobbing for real, hips stuttering, electricity crackling wild and uncontrolled over his skin. Akeru can feel it licking at his own field, feeding back into him, a feedback loop intense enough that his vision whites out at the edges of his bad eye.
It’s too much and not enough. Denki’s hips stutter, trying to thrust, but Akeru pins him gently with one hand splayed over his stomach, wings folding forward until the room is nothing but gold and black and the wet sounds of Akeru taking his little brother apart one careful lick at a time.
Denki comes with a sob, spilling over Akeru’s tongue, body lit up like a live wire. Akeru swallows every drop, throat working, wings flaring wide in pure, animal triumph before he catches himself and forces them down again.
He crawls back up Denki’s body, kissing him deep and slow, letting Denki taste himself on his tongue. Denki is crying quietly, clinging to him, legs still wrapped around Akeru’s waist like he’s afraid he’ll disappear.
“I’m sorry,” Akeru whispers again, pressing their foreheads together. “I’m sorry, I’m sorry-”
Denki shakes his head, frantic. “Don’t. Don’t be sorry. Please don’t be sorry.”
Akeru’s own cock is aching, trapped against Denki’s hip, leaking steadily into the fabric of his sweatpants. He could come just like this, grinding slow and filthy against his little brother’s thigh while Denki whimpers into his mouth, but he doesn’t. Not yet.
He reaches down between them instead, wraps a gentle hand around Denki’s softening length, and starts stroking again, slow and reverent, coaxing him back to hardness with soft murmurs and softer kisses.
Denki makes a broken sound. “Nii-san-”
“I know,” Akeru breathes. “I know. Let me take care of you. Just let me-”
He keeps going until Denki is hard again, oversensitive and trembling, until the second orgasm rips through him even harder than the first and he comes dry, clinging to Akeru like he’s the only solid thing in the world.
Only then does Akeru let himself go. He ruts against Denki’s thigh twice, three times, wings flaring so wide they knock over the desk lamp, and comes with Denki’s name on his tongue and tears in his eyes.
Afterward, they lie tangled together on the narrow mattress, Akeru’s wings curled protectively around them both like a cocoon. Denki is asleep almost instantly, exhausted, face pressed to Akeru’s throat, one hand still fisted weakly in the feathers at the base of his left wing.
“I love you,” Denki mumbles into his collarbone, voice wrecked. “I’ve always loved you. It’s okay, right? We’re okay?”
Akeru presses his face into Denki’s hair and lies, because it’s the only gentle thing left to do. “We’re okay.”
Akeru doesn’t sleep.
He stares at the ceiling and listens to Denki breathe and feels his instincts humming contentedly under his skin like a cat that finally caught the bird it’s been chasing for years.