The first thing Izuku becomes aware of is the heat. A solid, living warmth pressed along the entire line of his back, from shoulders to thighs. It’s a comfort so deep it feels woven into his bones, a stark contrast to the chill of rain-slicked fur he last remembers holding. The second thing is the weight. An arm, heavy and possessive, is slung over his waist, a broad hand splayed flat against his lower stomach. The third is the scent. Not rain, or cheap laundry detergent. Musk. The intimate, salty-sweet tang of his own spent arousal. His eyelids flutter, still heavy with sleep, his mind swimming up through layers of a dream that felt too real—hot, wet pressure between his legs, a voice growling ‘mine,’ pleasure that shattered him into pieces.
It was just a dream, he tells himself, the thought a desperate, hopeful whisper. A weird, stress-induced sex dream because he rescued a dog and he's lonely and his body does embarrassing things sometimes. He tries to shift, to curl into his pillow, but the warmth around him tightens. The arm over his waist pulls him back more firmly against a hard, unyielding chest. A soft, rumbling sound vibrates through his spine. A purr. Or a growl. Izuku freezes.
His eyes snap open.
The room is washed in the dull gray-blue light of early morning, his familiar walls coming into focus. His room. His bed. The proof of reality makes the solid, breathing body behind him impossible. A whimper catches in his throat. He looks down. A hand. A man’s hand, larger than his own, with calloused knuckles and long, sharp nails. It rests just below his navel, the tips of the fingers dipping into the soft trail of dark hair leading south. Every freckle on his stomach feels hyper-visible, every inch of skin screaming under that stationary, claiming touch.
The arm around his waist is an iron band, but Izuku manages, breath held, to twist his shoulders just enough. He turns his head on the pillow, a slow, aching pivot that brings the man behind him into view.
Ash-blond hair, spiky and wild even in sleep, halos a face that is all sharp angles and softened edges. High cheekbones, a strong jaw dusted with pale stubble, lips slightly parted with each deep, even breath. Long, pale lashes fan against his skin. He’s… beautiful. Rugged and carved and beautiful in a way that makes the air stutter in Izuku’s lungs. Tucked into the mussed hair are two pointed, furred ears, twitching faintly with some canine dream. Behind him, resting on the sheets, is a large, fluffy tail, the same ash-blond color.
This is the creature from his dream. The one who licked him apart. The one who growled ‘mine’ into his skin. This is Kacchan.
But that’s not what stops Izuku’s heart. It’s the shape of the brow. The set of the mouth, even in repose. A ghost from twenty years ago, pulled from the sun-drenched haze of a sandbox and stretched into a man. “No,” Izuku whispers, the word a dry crackle. His childhood friend. The bold, blazing boy who moved away before first grade, leaving only a phantom name Izuku had unconsciously given to a stray dog. Kacchan. This man looks like if that boy had grown up, hardened, perfected. If that boy had grown dog ears and a tail and crawled into his bed.
The logic of it is a dizzying spiral. The dog he found. The name he gave. The man now here. It can’t be. It’s insane. A coincidence warped by dream logic and loneliness. He’s still asleep. He has to be.
As if sensing his turmoil, the man—Kacchan—makes a low sound in his sleep. A soft, rumbling groan. His nose presses into the back of Izuku’s neck, inhaling deeply. The arm around Izuku’s waist tightens, pulling him flush against a chest that is all solid muscle and radiating heat. Izuku can feel every ridge of his abdomen, the hard line of his hips. And lower, pressed insistently against the curve of Izuku’s ass, the thick, undeniable heat of an erection. Even in sleep, he’s hard. Possessive. Claiming.
“You’re real,” Izuku breathes, not a question anymore. The evidence is imprinted on every nerve ending. The scent of them both, mingled. The weight. The heat. The slow, rhythmic puff of breath against his nape. The dream was a prelude. This is the waking reality.
Kacchan’s eyes snap open.
Crimson. Sharp, intelligent, and utterly feral. There’s no haze of sleep in them, only instant, predatory awareness. They focus on Izuku’s face, inches away on the pillow. Izuku doesn’t move. Can’t. He’s pinned by that gaze, a rabbit in a snare.
Kacchan’s lips curve, just slightly. Not a smile. A show of teeth. “Morning,” he rasps, his voice gravelly with sleep and deeper than Izuku expected. It vibrates through the space between them.
Izuku’s mouth works. A squeak emerges. Then, “You… you’re…”
“Kacchan.” He says it like it’s the only name that matters. His hand on Izuku’s stomach slides down, fingers splaying wider. There’s no fabric to stop them. Calluses scrape over the jut of his hip, then lower, dipping past the crease of his thigh. The touch is rough, proprietary. “Mate.”
Kacchan’s calloused fingers don’t hesitate. They slide past the crease of Izuku’s thigh, through the coarse hair, and find the desperate, slick heat waiting for them. A whimper tears from Izuku’s throat as a rough pad circles his clit, already hard and throbbing from the shock and the proximity and the memory of last night’s ruinous pleasure. “Nnh—!”
“Told you,” Kacchan rasps against the shell of his ear, his breath hot. His fingers are relentless, playing Izuku’s body like it’s already his instrument. “Mine. Gonna claim you proper now.”
Izuku’s mind is a static scream. The touch feels too good, a bright, sharp counterpoint to the panic tightening his chest. His hips jerk, a traitorous little thrust into that circling pressure. He’s naked. He’s wet, he can feel it, slickness coating Kacchan’s fingers, the obscene sound of it loud in the quiet room. This is insane. This is real. The dog he rescued is a man with his hand between his bare thighs.
“Feel how ready you are,” Kacchan growls, the words a vibration against Izuku’s spine. He grinds the thick, hard length of his erection against Izuku’s ass, a slow, deliberate roll that promises a stretch Izuku’s body can’t possibly comprehend. “Gonna fuck you full. Make you feel good. Like last night. Better.”
“Wait, I— Kacchan, your… it’s— it’s not—” Izuku babbles, his hands fluttering uselessly over the arm banded around his waist. He can’t form the thought. The shape of that hardness against him is all wrong. Too thick. Tapered wrong. The memory of a canine anatomy chart flashes, clinical and horrifying, in his vet-tech mind. The bulge of a knot. “It’s too big.”
Kacchan nuzzles his neck, a shockingly tender gesture at odds with the carnal promise of his words. “Fits. Made for you.” His middle finger, slick with Izuku’s arousal, pushes inside.
Izuku arches, a broken cry punched from his lungs. It’s not pain. It’s fullness, immediate and shocking, his body clenching around the intrusion. Kacchan’s finger is thick, the calluses scraping sensitive inner walls in a way that makes stars burst behind his eyelids. He’s being fingered open in his own bed by a creature from a dream, and his pussy is gripping him, pulling him deeper, begging for it.
“See?” Kacchan’s voice is dark with satisfaction. He crooks his finger, finds a spot that makes Izuku see white, and Izuku sobs. “Takes me so good. Gonna take all of me.”
He adds a second finger. The stretch burns, just for a second, a bright flare of *too much* before it melts into a deep, aching yield. Izuku’s head falls back against Kacchan’s shoulder, his body going pliant, betrayed by its own hunger. Kacchan scissors his fingers, working him open with a focused, ruthless efficiency. The wet sounds are filthy. Izuku wants to die from shame. He wants to cum from the sound alone.
“Please,” Izuku chokes out, not knowing what he’s asking for. Stop. Don’t stop. He’s scared. He’s so turned on he’s trembling. The two feelings are twin wires, pulled taut inside him.
“Please what?” Kacchan mouths at his throat, the words a hot vibration against his skin. His free hand comes up, fingers rough and seeking, to palm one of Izuku’s nipples. There’s no shirt now, nothing between the calloused touch and the tight, aching bud. Izuku jerks, a sharp gasp torn from him. The sensation is a bright, shocking wire straight to his groin. “Tell me.”
“I’m scared,” Izuku whispers, the admission raw and true. His eyes are squeezed shut. “You’re… you’re not human. It’s too much.”
Kacchan stills. The fingers inside him stop their relentless stroking, but they don’t withdraw. They just… stay. A claiming presence. “I’m yours,” he says, simple and absolute. “You saved me. Fed me. Kept me. My human.” He presses a blunt, hot kiss to the juncture of Izuku’s neck and shoulder. “I’ll be good to you. But I’m gonna claim you. Need to.”
The words shouldn’t soothe the panic. They do. A strange, primal part of Izuku settles at the declaration. *My human.* His fingers curl into the sheets. The stretch of Kacchan’s fingers inside him is becoming a sweet, heavy ache. A preview. His body is softening, accepting, preparing for what comes next even as his mind races. Kacchan feels it. He begins to move his fingers again, a slow, penetrating rhythm that steals the breath from Izuku’s lungs.
Kacchan’s fingers slip from Izuku’s body with a wet sound, and before Izuku can process the loss, a strong arm is hooking under his knee. He’s being rolled, the world tilting, until he’s flat on his back, the rumpled sheets cool against his heated skin. Kacchan moves over him, a solid shadow blocking the gray morning light, his crimson eyes gleaming with intent. He settles between Izuku’s spread thighs, his own impressive erection bobbing, flushed and thick and terrifyingly non-human, but he doesn’t press it forward. Instead, his calloused hands return to Izuku’s hips, holding him in place as two fingers find his soaked entrance and push back inside, deep and claiming.
“Kacchan—” Izuku gasps, his hands flying up to brace against the solid wall of the man’s chest.
The blonde’s head dips, his nose skimming the valley between Izuku’s small, heaving chest. “Let me hear it.” His mouth closes over one puffy, tight nipple.
Izuku’s cry is sharp and immediate, a raw, punched-out sound. Kacchan groans against his skin, the vibration a direct line to Izuku’s spine, and sucks harder. His tongue works the peak, rough and demanding, until the plea becomes a constant, broken stream from Izuku’s lips.
The sensation is electric, a sharp, wet heat that shoots straight to Izuku’s core. He cries out, back arching off the bed, his fingers tangling in spiky blond hair. Kacchan sucks, hard, his tongue flicking the peaked bud, while his fingers curl and stroke inside him, finding that devastating spot with unerring accuracy. The dual assault is too much. It’s everything. Izuku’s mind whites out, reduced to a feedback loop of *yes* and *more* and *please*.
“So good,” Izuku sobs, the words torn from him. He’s drowning in it, the pleasure a rising tide he has no hope of escaping. He doesn’t want to. His fears, the insane reality of it all, are being licked and fucked out of him. He keeps his eyes squeezed shut, refusing to look down at the evidence of what’s to come, choosing instead to exist solely in this blistering present.
Kacchan switches to his other nipple, lavishing it with the same rough, devoted attention, his fingers never ceasing their slow, deep penetration. The wet, filthy sounds of it fill the room, a soundtrack to Izuku’s unraveling. “Taste like mine,” Kacchan growls against his skin, the vibration making Izuku shudder. “Smell like mine. Gonna taste everywhere.”
He works his way down Izuku’s trembling stomach, nuzzling the trail of dark hair, his fingers finally withdrawing. Izuku makes a broken sound of protest at the emptiness, but it’s quickly swallowed by a gasp as Kacchan’s hot, wet tongue replaces them, licking a broad stripe over his dripping slit.
“Oh, god—”
“Not god,” Kacchan mutters, his breath fanning Izuku’s oversensitive flesh. “Kacchan.” And he seals his mouth over Izuku’s clit.
The orgasm hits Izuku like a seizure, violent and unexpected. His body bows, a silent scream locked in his throat as pleasure detonates through every nerve. He feels the gush of release, soaking Kacchan’s chin, the sheets beneath him. He pulses and clenches around nothing, desperate to be filled. Kacchan drinks it all down, lapping at him through the aftershocks, gentling his tongue until Izuku is a whimpering, boneless wreck.
Kacchan rises over him again, his own breathing ragged. His cock, slick with precum, rests heavy on Izuku’s thigh, the heat of it branding. Izuku can feel the distinct, thickened base. The knot. His stomach flutters with a fresh, dizzying wave of fear and want.
“See?” Kacchan whispers, his voice thick. He doesn’t move to enter. He just stares down, his face a mask of fierce restraint. The muscles in his arms are corded with the effort of holding still. “Good for you. Only good.”
Tears leak from the corners of Izuku’s eyes. He’s never felt so thoroughly ruined, so completely worshipped. He brings a shaking hand up to touch Kacchan’s jaw. “Why… why aren’t you…?”
Kacchan turns his head, pressing a kiss to Izuku’s palm. His crimson eyes are startlingly clear, the feral edge softened by something Izuku dares not name. “Scared you,” he says, the admission gruff. “My mate. Not a thing to break.” He lowers himself, resting his forehead against Izuku’s, their breath mingling. “You take me when you’re ready.”
The promise, and the terrifying patience in it, is what finally breaks Izuku open. A soft, shattered sound escapes him, and he pulls Kacchan down into a clumsy, desperate kiss.
The kiss isn't clumsy for long. Kacchan takes over, his mouth slanting over Izuku’s with a possessive, searing heat. His tongue pushes in, rough and demanding, and Izuku opens for it with a broken moan. It’s all salt skin and shared breath, the taste of himself—bitter and sweet—on Kacchan’s tongue. Izuku’s hands fist in spiky blond hair, holding on as the world narrows to the wet, frantic slide of their mouths, the scratch of stubble on his chin, the low growl vibrating from Kacchan’s chest into his own.
“Wait,” Izuku gasps, tearing his mouth away, chest heaving. His lips are swollen, already feeling used. Kacchan’s crimson eyes are blown dark, fixed on him. “I’m… I’m not ready. For that. Not yet.” His gaze flicks down, just for a heartbeat, to the thick, intimidating length resting on his thigh. “But… you should feel good, too. Please. Rub it. Against me.”
Kacchan stares at him, his breathing harsh. His jaw works. “Teasing,” he accuses, but there’s no real anger in it. A rough acknowledgment.
“Not teasing,” Izuku whispers, his heart hammering against his ribs. He guides Kacchan’s hips with trembling hands, the heat of the other man’s skin branding his palms. “Just… like this.”
Kacchan’s answer is another kiss, deeper, hungrier. He lets Izuku position him, the broad head of his cock dragging through the slick mess between Izuku’s thighs, catching on his folds but not pushing inside. The sensation is electric—a hot, blunt pressure against the most sensitive part of him. Izuku cries into Kacchan’s mouth, his hips jerking up instinctively.
“Mine,” Kacchan grunts against his lips, and then he starts to move. It’s not a gentle rocking. It’s a feral, desperate humping, his powerful hips driving his cock along Izuku’s soaked slit, over his throbbing clit, again and again. The friction is brutal, perfect. The swollen knot at the base drags against Izuku’s perineum with every thrust, a thick, tantalizing promise of what it will feel like inside.
The wet, slapping sounds are obscene. Izuku can’t stop the noises coming from his own throat—high, keening whimpers that match the frantic rhythm. His mind empties of everything but sensation: the scrape of Kacchan’s abs against his tender buds, the smell of sweat and sex and storm, the incredible heat of the cock gliding against his desperate, clenching entrance.
“Fuck, Izuku,” Kacchan snarls, burying his face in the crook of Izuku’s neck. His thrusts become harder, less controlled. His teeth graze skin. “So good. Your cunt’s so fuckin’ good.”
Izuku is sobbing, his legs wrapping around Kacchan’s waist, heels digging into the small of his back. He’s not being filled, but he’s being claimed just as thoroughly, branded by the relentless slide. His own arousal is a flood, making everything slicker, hotter, the sounds even filthier. He can feel Kacchan’s entire body tightening, the muscles in his back and arms corded like steel.
“Gonna come,” Kacchan warns, the words a hot, ragged puff against Izuku’s ear. His rhythm stutters, becomes frantic, grinding rather than thrusting. “On you. Mark you.”
“Yes,” Izuku chokes out, his own climax coiling tight, sparked by the friction and the raw possession in that growl. “Kacchan, please—”
Kacchan’s body locks. A rough, shattered sound tears from his throat. Izuku feels the hot, sudden pulse of release against his lower belly, his pussy, a scalding stripe of it. The scent, musky and primal, hits the air. The sensation triggers Izuku’s own undoing—his back arches off the bed, a silent scream on his lips as he spasms, soaking them both all over again.
Kacchan shifts above him, pulling back from the spent, panting collapse of their bodies. His crimson eyes are dark, feral, but focused. He doesn't look satisfied. He looks like he's just begun.
"Not enough," Kacchan grunts, his voice rough. He braces himself on his arms, kneeling over Izuku's trembling form, his gaze sweeping over the mess of sweat and spend marking Izuku's skin. "Need to claim. Fully."
"What—" Izuku starts, his voice a raw scrape, but the question dies as Kacchan's hand moves to his own thick cock, still slick and half-hard. He doesn't stroke it. He aims it.
Izuku's brain stutters, tries to reject what it's seeing. *He's not— he can't be—* A hot, golden stream arcs out, hitting Izuku's chest with a shocking, intimate splash. It's scalding. It smells sharp, musky, animal. Izuku flinches, a choked gasp escaping him as the piss soaks his small buds, rolls down the valley between them, tracing paths through his freckles.
"Kacchan, stop!" Izuku cries, his hands coming up to shield his face, but he doesn't push him away. His body is frozen, caught between horror and a terrifying, humiliating curiosity. The heat is… everywhere.
"Mine," Kacchan says, the word a low growl of pure intent. He adjusts his angle, the stream moving lower, painting a hot line down Izuku's quivering stomach, over the mess of his own release, heading inexorably lower. "Mark you. Inside and out."
The hot spray hits his pussy directly, a concentrated torrent against his swollen, oversensitive clit. Izuku screams. It's not a scream of pain. It's a sharp, shattered sound of electric sensation, a white-hot jolt that bypasses every rational thought and goes straight to his core. His back arches violently off the bed, his hips bucking into the stream as if seeking more.
"See?" Kacchan breathes, watching him with rapt, possessive intensity. The piss is a relentless, claiming rain, mixing with the slick and spend already there, a filthy baptism. "Your body knows. Knows its mate."
Izuku is sobbing, tears mixing with the wetness on his face. He's horrified. He's aroused beyond bearing. The scalding pressure on his clit is a brutal, perfect friction, and his traitorous body seizes, clamping down on nothing. A gush of clear fluid, his own squirt, erupts from him, mingling violently with Kacchan's stream, splashing back against Kacchan's cock and thighs.
Kacchan lets out a sharp, satisfied sound. "Marking me back," he says, and there's awe in his rough voice. He finally stops, the last few drops pattering onto Izuku's trembling thighs. The room fills with a thick, primal scent—ozone, sex, and now this deep, animal musk. Kacchan sits back on his heels, looking down at his work. Izuku is drenched, glistening, utterly claimed.
Izuku can't speak. He can only breathe in ragged, shuddering gulps. His skin is on fire. His pussy is throbbing, clenching around a phantom fullness. He feels wild. Owned. He whimpers, covering his face with his hands. "We… we need a bath. Now. We smell…"
Kacchan's expression darkens instantly, a low growl rumbling in his chest. "No. My scent. On you. It stays."
"Kacchan, please," Izuku begs, peeking through his fingers. The smell *is* overpowering. It's also, shamefully, making his head spin. "Just a bath. You… you can do it again after. Later." The promise falls from his lips, a desperate bargain, and the truth of it burns worse than the piss had. He *wants* the promise. He wants the shameful, hot claim of it.
The growl cuts off. Kacchan cocks his head, his dog ears twitching. He studies Izuku's flushed, tear-streaked face, the way his body still shivers with residual sensation. "Later," he repeats, testing the word. He leans down, nostrils flaring as he inhales deeply the scent of his mate, marked by him. A slow, possessive smile curves his lips. "Okay. Now bath. Then more later.”