The cabin floor was hard, but the dawn light was soft, and for hours they slept tangled in the exhaustion of the night before.

Katsuki woke first, his back protesting against the wood, Izuku a warm, familiar weight against his chest. He didn’t move. He watched the dust motes drift in the thin morning sun slicing through the blinds, his hand resting on the dip of Izuku’s waist. The world outside was silent. The camp, for now, was still.

Izuku stirred, nuzzling into the solid muscle of Katsuki’s pec. “Daddy?” His voice was sleep-rough, a bare whisper.

“Yeah, nerd.”

“We’re still here.”

“We’re still here.”

They didn’t get up. The day stretched, empty and theirs. Katsuki shifted them to the ruined bed, the sheets smelling of sex and sweat, and they lay in the quiet. He traced the freckles on Izuku’s shoulder. Izuku pressed lazy, open-mouthed kisses to his collarbone. It was slow. It was tender in a way that made Katsuki’s chest feel too tight.

“Just kiss me,” Izuku murmured, tilting his face up. “Just for a while.”

Katsuki did. He kissed him slow and deep, tasting sleep and the ghost of himself on Izuku’s tongue. It was lazy. It was supposed to be easy. But Izuku’s hand slid down Katsuki’s stomach, his fingers brushing the thatch of hair below his navel, and the kiss broke on a shared, sharp inhale.

“Izuku,” Katsuki warned, but it was weak.

“I need it,” Izuku whispered against his mouth, his hips making a small, desperate circle in the air. “I’m empty, Daddy. I can feel where you were, and it’s empty.”

“You’re sore.”

“I don’t care.” Izuku pushed back the thin sheet, the cool cabin air hitting their skin. He looked down at himself, at the mess between his legs, then back at Katsuki with green eyes gone dark. “Look.”

He moved before Katsuki could stop him. He hooked his hands behind his knees, his body flexible from years of training, and pulled his legs up and back. He folded himself, presenting himself, putting his swollen, hairless cunt on obscene display. It was reddened, used, and a trickle of milky white spend seeped from the fluttering opening, tracing a path down to the sheets.

“It’s still dripping you,” Izuku breathed, his voice shaking. “See? It’s still hungry. It needs you to fill it up again.”

Katsuki’s vision tunneled. Every ounce of blood in his body surged south, a violent, instant pull. His cock, heavy and soft against his thigh, jerked to life so fast it was a pain, a throbbing, insistent ache. It thickened, lengthened, rising untouched to press against his stomach, uncut and already leaking at the tip. It was the hardest he’d ever been, a brutal, primal response to the sight and the words.

“Please, Daddy,” Izuku begged, his hips canting up, offering himself. “Please fuck me. I need your cock. I need you to breed this tiny boy pussy. Fill me up. Put a baby in me. Make me a mommy, Daddy, please, make me a mommy.”

The thick, heavy weight of his cock slapped against Izuku's swollen flesh with a wet, meaty sound. Katsuki held himself there, letting the heat of Izuku's body seep into him, then dragged the broad head up through the slick mess, painting his son's clit with his own spend before slapping down again. Harder.

Izuku cried out, his back arching off the bed. "Daddy!"

"You see this?" Katsuki growled, his voice shredded. He pulled back and shook his cock, side to side, the leaking tip flicking brutally against Izuku's throbbing clit with each pass. "This is what you begged for. This is what your hungry little cunt woke up."

"Yes! Yes, please!"

"Beg more." Katsuki pressed the blunt head right at his entrance, applying just enough pressure to make Izuku's hips jerk. He didn't push in. Not yet. "Use your words, nerd. What do you want Daddy to do to this boy pussy?"

Izuku's breath hitched, his green eyes wide and fixed on Katsuki's face. "I want… I want you to fuck it raw. Just your skin inside mine."

"And?"

"I want you to fill it up. I want to feel you come so deep I taste it in my throat." Izuku's hands tightened behind his knees, spreading himself wider. A fresh trickle of clear arousal mixed with the white. "I want your cum dripping out of me for days. I want everyone to smell you on me."

Katsuki's cock pulsed, a fresh bead of pre-come welling and dropping onto Izuku's clit. "Keep going."

"Breed me," Izuku moaned, the words tumbling out in a desperate stream. "Please, Daddy, breed my cunny. Shoot it all the way up into my womb. Knock me up. I want your baby so bad. I want my belly to swell with it. I want everyone to know my Daddy owns me, that he put his son in me. Make me a mommy. Make me your good boy mommy, please, I need it—"

Katsuki’s control snapped. A rough, animal sound tore from his chest. He leaned forward, caging Izuku with his arms, his cock notching perfectly at that fluttering, soaked entrance. The head pressed in, just an inch, the stretch immediate and perfect.

Izuku sobbed, his legs trembling where they were hooked behind his head. "Daddy…"

"You feel that?" Katsuki grit out, his hips shuddering with the effort of not slamming home. "That's where I'm gonna put it. Every last drop. You're gonna take it all, aren't you? My good boy?"

"Yes! I'll take it, I'll take all of it, just please, fill me up—"

Katsuki drove forward.

It wasn't gentle. It was a single, brutal thrust that buried him to the root, sheathing his entire length in the clutching, scalding heat of his son's body. Izuku screamed, a raw, broken sound that echoed off the cabin walls. His cunt clamped down, a vise grip of slick muscle, milking Katsuki's cock on the way in.

"Fuck," Katsuki choked, his forehead dropping to Izuku's shoulder. "Fuck, Izuku."

"You're so deep," Izuku whimpered, his body shaking. "I can feel you in my stomach, Daddy. It's so full."

Katsuki didn't move. He let them both feel it. The complete possession. The obscene stretch. The hot, wet slide of his own spend being pushed deeper as Izuku's pussy desperately tried to accommodate his girth. He turned his head, his lips finding Izuku's ear.

"You want me to breed this cunt?" he whispered, his voice a dark promise. "Then take it. Take every inch. And when I come, you're gonna thank me for it."

Katsuki set a brutal, punishing pace, his hips pistoning, driving his cock so deep into Izuku's clutching heat that the head bumped against something tight and internal with every thrust. The wet, slapping sound of their joining filled the cabin, rhythmic and obscene.

"Watch," Katsuki growled, his voice ragged. He hooked a hand under Izuku's knee, forcing his leg wider, angling himself even deeper. "Watch Daddy rearrange your guts. See how your belly jumps?"

Izuku’s tear-filled eyes dropped to his own lower stomach. With every deep, grinding push, a slight bulge distended his soft flesh. "Daddy—"

"That's my cock," Katsuki snarled, leaning over him, driving in harder. "That's me in your womb, you greedy little slut. I'm gonna fuck a baby so deep into you, you'll feel me for nine months."

Izuku sobbed, his cunt clenching in a spasmodic rhythm around the invading thickness. "Yes! Do it, please, breed me—"

A sharp, electronic buzz cut through the sounds of sex and skin. It vibrated against the wooden floorboards where Katsuki’s discarded pants lay.

Katsuki didn't stop. He didn't even slow. He kept fucking into Izuku with the same relentless, cervix-punishing rhythm, his balls slapping wetly against his son's ass.

"Phone," Izuku gasped, his head thrashing side to side.

"I know." With a grunt, Katsuki leaned back, one hand still braced on Izuku's thigh, the other groping blindly for his pants. He found the buzzing device, fumbled it, and brought the screen to his face. A flicker of something dark and amused crossed his features. He swiped to answer and tapped the speaker icon.

"Hello?" he said, his voice only slightly strained. He pulled Izuku's hips up and drove back in, a particularly deep thrust that made the bedframe creak.

"Katsuki, honey! I was just checking in." Inko's cheerful, warm voice floated into the room, tiny through the speaker. "How's camp going? The weather looked iffy on the news."

Izuku froze beneath him, his cunt clamping down in a vice-grip of panic. Katsuki hissed, his hips stuttering for a second before he resumed, rolling his own in a slow, deliberate grind that pulled a muffled whimper from Izuku's bitten lips.

"It's fine," Katsuki said, his eyes locked on Izuku's horrified, flushed face. "Rain yesterday. Clear today. The kids are…" He thrust, hard. "...running drills."

"Oh, good! And Izuku? Is he adjusting alright?"

Katsuki smirked, a devious, cruel thing. He leaned down, his mouth hovering over Izuku's. "He's adjusting perfectly," he said into the phone, his gaze burning into his son's. "Aren't you, Izuku?"

Izuku's eyes widened. He shook his head frantically, a silent plea.

"Katsuki? Is he there?" Inko asked.

"He's right here," Katsuki said, his voice dropping to a low, intimate rumble meant only for the room. He punctuated the sentence with a sharp, shallow thrust that made Izuku's breath hitch audibly. "Say hello to your mom, baby."

The command was a live wire. Izuku stared up at him, terror and dizzying arousal warring in his green eyes. Katsuki didn't stop moving inside him.

"H-hi, Mom," Izuku squeaked out, his voice thin and trembling.

"Izuku! You sound out of breath, sweetie. Are you coming down with something?"

Katsuki’s grin was feral. He picked up the pace again, the wet sounds becoming unmistakable. Izuku slapped a hand over his own mouth, his body bowing with the force of the fucking.

"He's just… worn out from practice," Katsuki supplied, his own breathing growing heavier. "I'm working him… very hard."

"Well, don't be too hard on him! He tries so hard to impress you, you know."

"Oh, I know," Katsuki breathed, his eyes glazing over as he felt Izuku's pussy begin to flutter and drip around him. "He's being very… obedient. Taking everything I give him."

"That's my boy! Okay, I'll let you two get back to it. Love you both!"

"Love you too," Katsuki said, the words a dark parody of tenderness. He ended the call and tossed the phone aside. It clattered on the floor. The second the connection broke, the silence was filled with the raw, unfiltered noise of their sex: grunts, slaps, and the slick, rhythmic squelch of his cock plunging into a soaked, tightening cunt.

"You… you…" Izuku panted, his hand falling away from his mouth.

"I what?" Katsuki drove into him, deep and unrelenting. "She heard you. She heard how good Daddy's cock feels.”

"She heard every wet sound your cunt makes," Katsuki growled, his hips never breaking their brutal rhythm. "Heard you trying not to scream while her husband's cock split you open."

Izuku whimpered, his nails digging into Katsuki's forearms. The shame was a hot, oily wave, but it crested into a sharper, more desperate need. "Daddy—"

"She thinks you're my good boy," Katsuki snarled, leaning close, his breath hot against Izuku's ear. "She has no idea you're my greedy little slut, begging for her daddy's seed. That her son's pussy is dripping with it right now."

"Stop," Izuku sobbed, but his hips arched up, taking Katsuki deeper. "Please, stop saying it—"

"Why?" Katsuki bit his earlobe, a sharp, possessive sting. "It's the truth. We're animals. I'm fucking my son. And your mother just gave us her blessing." He punctuated the last word with a thrust so deep Izuku saw stars. "You liked it. Don't lie. I felt you clench."

Izuku's head thrashed against the pillow. He couldn't deny it. The terror had been electric, a live wire that supercharged every nerve. "It's wrong."

"Everything about this is wrong," Katsuki agreed, his voice a dark, thrilling rasp. "Your tiny tits. This swollen cunt. The way you look at me." He slid a hand between them, his thumb finding Izuku's clit, rubbing hard, cruel circles. "You were built for this. Built for me to ruin."

"This is why I fucked your mother," Katsuki snarled, his voice a raw scrape against Izuku's ear. His hips pistoned, each thrust a brutal punctuation. "This filthy, hungry cunt. This is the only reason we had a baby. I made you for this. To be Daddy's slutty fuck toy."

Izuku cried out, a broken sound that was half-sob, half-moan. His fingers clawed at the sheets.

"You were born from my nuts," Katsuki growled, his breath hot. "My seed made you, just so I'd have a tight, tiny boy pussy to wreck. My own personal free-use whore."

"Daddy—"

"Say it," Katsuki commanded, his thumb digging into Izuku's clit. "Tell me why you exist."

Izuku's face was wet with tears and sweat. His green eyes were glazed, unfocused with shame and a pleasure so deep it bordered on pain. "T-to be… your whore."

"My son. My whore." Katsuki kissed him, a hard, claiming press of lips. "Everything you are is mine. Your brain, your body, this dripping cunt. I own it. I made it."

He felt the orgasm building in Izuku, the frantic fluttering around his cock, the way his son's thighs began to shake. He didn't let up. He fucked him through the trembling, through the choked-off screams, driving him straight over the edge. Izuku came with a shattered cry, his back arching off the bed, a fresh gush of wetness soaking the sheets beneath them.

Katsuki followed, his own release ripped from him by the violent clenching of Izuku's body. He buried himself to the hilt, grinding deep as he emptied into him, a low, animal groan tearing from his throat. He collapsed forward, his weight pressing Izuku into the mattress, both of them panting, slick with sweat.

For a long moment, there was only the sound of their ragged breathing. Then Katsuki shifted, pulling out slowly. The sight made his spent cock twitch: Izuku, wrecked and pliant, his hole leaking white onto the ruined sheets.

Izuku turned his head, his cheek against the pillow. His voice was a hoarse whisper. "You really think that?"

"Think what?" Katsuki traced a finger through the mess on Izuku's inner thigh.

"That you… made me for this."

Katsuki looked at him. The post-coital haze was clearing, leaving something colder, more terrifying in its honesty. "Yeah. I do." He brought his finger to his mouth, tasting salt and himself. "I looked at you in that fucking uniform and I knew. Every instinct I ever had to protect you, to keep you away… it was just me trying to hide from what I really wanted."

Izuku shivered. He didn't look away. "So what happens when we go home?"

"We lie." Katsuki's voice was flat. Final. "We lie to your mother every day for the rest of our lives. And you come to my office after practice. And I fuck my son on my desk."

A slow, trembling breath escaped Izuku. He didn't protest. His hand crept across the mattress, his fingers brushing Katsuki's. "Okay."