The only sound in the dark room was Shoto’s deep, even breathing and a steady rhythm from the other side of the queen-sized bed. Izuku lay rigid between his sleeping boyfriend and the edge, every nerve screaming. The dose had been careful, calculated. It would hold. It had to. The weight beside him shifted, the mattress dipping, and a large, calloused hand slid over his hip, pulling him back against a hard, familiar heat.

“Uncle Kacchan,” Izuku breathed, the title a shaky exhale against the pillow.

“Shut up and move,” Katsuki’s voice was a guttural rasp in his ear, hot and demanding. He yanked down Izuku’s sleep shorts and his own boxers in one rough motion. There was no preamble, no slow entry. Katsuki’s thick, leaking cockhead nudged against Izuku’s hole, already slick and loose from anticipation. He shoved in.

Izuku’s back arched, a silent scream tearing through his throat as he was filled in one brutal, stretching thrust. He buried his face in the pillow to stifle the cry, his body convulsing around the invasion. It was too much, it was everything. Katsuki didn’t wait, setting a punishing, deep rhythm immediately, his hips pistoning against Izuku’s ass with wet, rhythmic slaps.

“That’s it,” Katsuki grunted, his mouth mashed against the side of Izuku’s neck, biting down on the freckled skin. “Take it. In your own bed. Right next to your pretty little boyfriend.”

“He’s—ah!—sleeping,” Izuku gasped, the words breaking apart as Katsuki angled deeper, hitting a spot that made white light flash behind his eyelids.

“He’s fucking oblivious,” Katsuki snarled, his hand snaking around to grip Izuku’s small chest, pinching a puffy nipple hard. “Dreaming about his perfect future. Doesn’t know his prince is getting his fucking brains fucked out by his uncle.” He punctuated each filthy word with a driving thrust. “Your cunt’s sopping. Dripping for me. Bet you’ve been wet since we slipped him the pill.”

Izuku couldn’t deny it. He was drowning in it—the illicit thrill, the overwhelming stretch, the sheer wrongness that wired his pleasure directly to his core. He pushed back, meeting Katsuki’s thrusts, a quiet, desperate moan leaking into his pillow. “Kacchan… please…”

“Please what, nerd?” Katsuki’s breath was ragged. “Gonna squirt for me? Gonna soak your childhood sheets while your boyfriend sleeps two feet away?”

The coil in Izuku’s gut tightened violently. His thighs trembled, a familiar, helpless pressure building. “I’m—I’m gonna—”

“Do it.” Katsuki’s command was absolute. He slammed in, hilt-deep, and ground his hips in a vicious circle. “Cum. Let him hear what a slut you are for your uncle’s cock.”

The orgasm ripped through Izuku without permission. It was a silent, cataclysmic burst, a gush of fluid soaking the sheets beneath them, his body seizing around Katsuki in relentless, fluttering pulses. He shook, utterly wrecked, a choked sob of pleasure and shame caught in his throat.

Katsuki groaned, low and feral, his rhythm stuttering. “Fuck. Fuck, just like that.”

Katsuki’s hips stilled, buried deep. He gripped Izuku’s shoulder and flipped him onto his back with a rough, possessive strength. The movement shoved Izuku higher on the mattress, his head coming to rest near Shoto’s sleeping hand. Katsuki loomed over him, braced on his arms, his cock still seated inside Izuku’s slick, fluttering heat. The dim light from the hall caught the sweat on Katsuki’s chest, the desperate hunger in his red eyes as he stared down at Izuku’s wrecked, tear-streaked face.

“Look at you,” Katsuki breathed, his voice shredded. He began to move again, a slow, deep, dragging withdrawal followed by a relentless push. “Wanted to see you like this. In this stupid bed.”

Izuku’s hands scrabbled at Katsuki’s biceps, his mouth open on silent, hitching gasps. He could feel Shoto’s warmth radiating beside him.

“Ever since you were a fuckin’ teenager,” Katsuki growled, the pace punishing and deliberate. “Since your little tits first popped out.” He dropped his head, his mouth latching onto one puffy nipple, sucking hard before biting down. His other hand pinched and twisted the other. “You’d run around in tank tops, thinking I didn’t notice. I noticed.”

A sharp, bright bolt of pleasure-pain shot through Izuku’s core. His back arched off the mattress, a choked “Kacchan!” escaping as a wet, hot gush spilled from him, soaking the sheets beneath his ass. The orgasm was swift and brutal, milking Katsuki’s cock inside him.

Katsuki groaned against his skin, never stopping his thrusts. “Your first boyfriend. That shitty extra from your class.” His rhythm became jagged, angry. “Heard you. In here. The night you lost it.” He leaned closer, his nose brushing Izuku’s. “Should’ve been me. That should’ve been my cock you took.”

“It should’ve,” Izuku sobbed, the admission torn from him. The coil tightened again, impossibly fast. He shook as another wave of release rushed out of him, a silent, soaking flood. “I wanted… I wanted it to be you.”

“Prom.” Katsuki snarled the word like a curse. His hand came up to cradle Izuku’s jaw, his thumb smearing across his lower lip. “You painted your face. Looked like a cheap whore. Wanted to ruin you for it. Wanted to fuck this pretty mouth until your makeup ran and you couldn’t speak.”

Izuku turned his head, catching Katsuki’s thumb in his mouth, sucking it desperately. His hips rocked up, meeting each deep drive. He came again, a third time, his body convulsing in a continuous, dripping shudder. “Yes,” he whimpered around the digit. “Wanted that too.”

Katsuki pulled his thumb free, slick with spit. His control was fraying, his thrusts losing their measured pace. “Graduation party. You were leavin’. Didn’t know when I’d see you again.” He dropped his forehead to Izuku’s, their breath mingling. “Wanted to drag you up here and make you cum so many times you’d feel me for a week. So you’d remember who you belonged to every time you sat down in some fancy college class.”

“Kacchan, please,” Izuku begged, tears streaming into his hairline. The confession unlocked something deeper, a raw need that had festered for years. His fourth climax wasn’t a gush but a torrent, soaking them both, his cunt clamping down in rhythmic, greedy pulses. “I dreamed about it. I touched myself thinking about you that night.”

“Every holiday,” Katsuki gasped, his hips stuttering. He was close, his whole body trembling with the effort to hold back. “Every goddamn time you came home. Wanted to come in here every night and fuck the living daylights out of you while your parents slept downstairs.” He finally broke, his rhythm dissolving into frantic, shallow pumps. “Wanted you. Always. Fuck.”

Izuku wrapped his legs around Katsuki’s waist, locking his ankles. “Now,” he pleaded, his voice a broken whisper. “Have me now. Always.”

That was all it took. Katsuki’s orgasm ripped through him with a stifled, guttural roar. He shoved in to the hilt and held, his body bowing taut as he emptied himself deep inside Izuku in hot, pulsing streams. Izuku felt the flood, the intimate claim, and it triggered his own fifth, final release, a weak, continuous seep of pleasure that left him boneless and trembling.

For a long minute, the only sounds were their ragged breaths and Shoto’s undisturbed snores. Katsuki collapsed onto him, his weight a crushing, comforting anchor. He nuzzled into the sweat-damp curls at Izuku’s temple.

“Nerd,” he murmured, the word thick with an emotion neither would name.

Izuku’s hands came up, stroking the sweat-slick planes of Katsuki’s back. He felt ruined, hollowed out, and more seen than he ever had in his life. The shame was there, a cold knot in his stomach, but it was drowned under the warmth of the body on his and the honesty hanging in the dark air.

“What do we do?” Izuku whispered, the question aimed at the ceiling.

Katsuki was silent for a beat. Then he shifted, pulling out slowly. Izuku winced at the sudden emptiness, the wet, sticky evidence between his thighs. Katsuki rolled onto his side, facing him, one heavy arm draping over Izuku’s waist. His crimson eyes were dark, unreadable in the near-darkness.

“We survive ‘til Christmas,” Katsuki said, his voice low and final. “Then we stop.”

Izuku turned his head to look at Shoto’s peaceful profile. The ring box was in Shoto’s suitcase. He knew it was. He looked back at his uncle. “Yeah,” he lied, the word ash in his mouth. “Then we stop.”