The door is open. Katsuki stands in the frame, a solid silhouette against the hall light. He doesn’t move to close it. His eyes, sharp and red, take in the scene: his son collapsed on the soaked sheets, chest heaving, the vibrator still buzzing faintly on the mattress beside his thigh.

Izuku can’t breathe. He can’t move. He just stares, frozen in the wreckage of his own climax, his father’s gaze a physical weight on his naked skin.

Katsuki steps inside. The floor doesn’t creak. He moves with a predator’s quiet, his focus absolute. He doesn’t look at Izuku’s face. He looks at the toy.

He reaches down, his scarred fingers closing around the plastic. The buzzing stops as he lifts it. He turns it over in his hand, examining the slickness glistening in the low light.

“Pathetic,” Katsuki says, his voice a low rumble. Not angry. Amused.

Izuku flinches. A whimper catches in his throat.

Katsuki’s thumb finds the dial. He clicks it once, twice. The motor whirs back to life, a soft purr. Then he clicks it again. And again. The pitch climbs, sharpening into a frantic, aggressive buzz that fills the silent room.

He smirks. It’s a dark, knowing thing. “You’re doing it wrong, kid.”

“D-Daddy—”

“Let me help you with that, baby.”

Before Izuku can process the words, the hand that isn’t holding the toy is on his knee. Katsuki’s palm is searing hot. He pushes, and Izuku’s legs fall open, exposing him completely. The cold air hits his wet cunt and he jerks.

Katsuki doesn’t hesitate. He doesn’t ask. He pushes the vibrator back inside.

Izuku gasps, back arching off the bed. It’s not the slow, searching push from his own hand. It’s a firm, deliberate invasion, the plastic still warm from his body but now controlled by his father. The vibration is immense, a brutal thrum that radiates up his spine instantly.

“See?” Katsuki says, his voice close now. He’s leaning over the bed, his other hand planting itself on the mattress beside Izuku’s head, caging him in. “You gotta use the settings.”

He starts to move it. Not a gentle rocking. A hard, piston-like fuck, driving the toy deep into Izuku’s cunt and pulling it almost all the way out before slamming it back in. The wet, slapping sound is obscenely loud. The vibration blurs into a continuous, devastating roar inside him.

Izuku’s hands fly out, scrambling for purchase. They find his father’s forearm, the corded muscle under his skin rigid and unmoving. He’s so strong. Izuku’s nails dig in, but Katsuki doesn’t even seem to feel it.

“That’s it,” Katsuki grunts, his breath hot against Izuku’s temple. His rhythm is relentless, perfectly timed to the most sensitive spots Izuku himself could never quite find. “Take it. You wanted it, didn’t you? Making a fucking mess.”

Tears spill from Izuku’s eyes. He’s nodding, a frantic, broken motion. He can’t speak. His hips are lifting off the bed to meet every thrust, his body betraying every shred of shame. It’s too much. It’s not enough.

“Look at you,” Katsuki murmurs, his crimson eyes locked on where their bodies are connected, on the toy he’s wielding. “Soaked. Dripping all over the sheets. My good boy.”

The words—*my good boy*—unravel him. A choked sob rips from Izuku’s throat as the pleasure crests, violent and immediate, tearing through his core. He comes, his cunt clenching viciously around the vibrating intrusion, a fresh gush of fluid spilling out around the plastic. His vision whites out.

Katsuki doesn’t stop. He fucks him through it, the toy still buzzing at max power, dragging the orgasm out into a shuddering, endless wave of overstimulation. Izuku is screaming, a raw, ragged sound, his body convulsing.

Katsuki doesn’t stop. The vibrator is a relentless, buzzing extension of his will, pistoning in and out of Izuku’s oversensitive cunt. The wet, slapping rhythm is the only sound besides Izuku’s ragged, sobbing breaths.

“Look at this mess,” Katsuki says, his voice a low, conversational rumble against Izuku’s ear. He doesn’t sound winded. He sounds like he’s observing the weather. “Hormones really got you by the throat, huh, kid? Constantly wet. Needing to fuck this pretty cunt until you’re squirting everywhere.”

Izuku whimpers, his hips twitching helplessly. Every nerve is raw, screaming. The pleasure has tipped into a sharp, unbearable ache, but his body keeps clenching, trying to pull the toy deeper.

“Daddy—”

“Shh. I got you.” Katsuki’s free hand comes up, not to comfort, but to grip Izuku’s jaw, forcing his head to the side so their eyes meet. His thumb smears a tear across Izuku’s cheekbone. “This is what fathers are for. Helping their sons get off. You don’t have to do it alone in the dark anymore.”

He says it like it’s simple. A fact. Like he’s teaching him to shave. The absurdity of it drowns Izuku more than the sensation between his legs.

“You must have been so horny,” Katsuki continues, his crimson gaze dropping to watch his own hand work. “Dreaming about it. Touching yourself in class, probably. I see how you look sometimes.”

Izuku’s eyes widen. A fresh wave of shame, hot and nauseating, crashes over him. He shakes his head, a frantic denial that gets lost in another choked gasp as Katsuki angles the toy, hitting a spot that makes his vision spark.

“Don’t lie,” Katsuki murmurs, his grip on Izuku’s jaw tightening just enough to feel like a threat. “It’s normal. Your body’s changing. It wants things. And I’m here to give them to you. Any toy you need. My hand. Whatever.”

He punctuates the last word with a particularly deep, grinding thrust that forces a broken cry from Izuku’s throat. The orgasm is building again, a terrifying tsunami gathering in his gut, pulled to the surface by his father’s unwavering, clinical attention.

“That’s it,” Katsuki encourages, his voice dropping to a rough whisper. “Let it go. Show me how good it feels when Daddy helps.”

Izuku shatters. The climax isn’t a wave this time; it’s a detonation. His back arches off the bed, a silent scream locked in his chest as his cunt convulses, gushing around the vibrating plastic. It feels endless, a violent expulsion of slick fluid that soaks his thighs and the sheets beneath him with a hot, audible rush.

Katsuki watches it happen, his expression one of intense, focused satisfaction. He finally stills the toy, leaving it buried deep as Izuku’s body jerks through the aftershocks. He leans close, his lips brushing the shell of Izuku’s ear.

“See?” he says, quiet and final. “Better when I do it.”

Katsuki doesn’t pull the toy out. Instead, he shifts his weight, the mattress dipping as he stretches out beside Izuku’s trembling body. The vibrator still buried deep, his hand resting possessively between Izuku’s thighs. He begins to roll it in a slow, deliberate circle inside him, the relentless buzz now a low, internal hum.

“You want Daddy to make you come more?” Katsuki asks, his voice a rough murmur in the dark. His other hand comes up, fingers brushing the damp hair from Izuku’s forehead before he leans down and presses a kiss there. It’s tender. Absurdly sweet.

Izuku whimpers, a broken sound. His body is a live wire, oversensitive and raw, yet the slow, circling motion is already coaxing a fresh, treacherous throb from his core. He nods, a jerky movement.

“Use your words, baby.”

“Y-Yes,” Izuku chokes out.

“Yes, what?”

“Yes… Daddy.”

Katsuki hums, satisfied. He starts to move the toy again, not the brutal pistoning from before, but a slow, grinding fuck, pushing it in and out with a measured rhythm that makes Izuku’s toes curl. “Good boy. Now tell me. How can Daddy help? What do you need?”

Izuku’s breath hitches. The slow, grinding motion of the toy is a sweet, unbearable torture. He turns his face into the pillow, his voice muffled and raw. “Just… hold me. Keep going.”

Katsuki’s hand stills. The buzzing inside Izuku becomes a constant, waiting hum. “That’s all?”

“Please.”

Katsuki shifts, his body a solid line of heat along Izuku’s side. His arm slides under Izuku’s neck, pulling him close until Izuku’s back is flush against his father’s chest. He can feel the hard planes of Katsuki’s torso, the beat of his heart against his spine. Katsuki’s other hand resumes its work, the toy beginning its slow, deep circles again.

“Like this?” Katsuki murmurs into his hair.

Izuku nods, a frantic little movement. He’s trembling. Being held like this, caged and safe, is worse. It’s better. It cracks something open in his chest.

“You’re shaking.” Katsuki’s lips brush the shell of his ear. “Why?”

“I don’t know.”

“Don’t worry, baby. Daddy’s got you,” Katsuki murmurs, his lips brushing Izuku’s temple. The kiss is soft, paternal. His hand between Izuku’s thighs begins to move again, the toy sliding out slowly before pushing back in with a deliberate, building rhythm. “Just helping my boy feel good. That’s all.”

Izuku shudders, a full-body tremor that has nothing to do with cold. The tenderness is a worse violation than the roughness. It makes the thing inside him feel like a gift.

“You’re so tense,” Katsuki observes, his voice a low rumble against Izuku’s ear. His other hand strokes down Izuku’s arm, a soothing motion. “Relax. Let Daddy take care of it.”

He increases the pace, the toy fucking into Izuku with a wet, rhythmic sound. The vibration is a constant, maddening buzz deep in his core, coaxing another wave of heat to the surface despite the oversensitivity.

“Is my boy gonna come again?” Katsuki asks, his tone conversational, almost curious. He nuzzles into Izuku’s hair, his breath warm. “You feel so tight around this. Clenching like you’re trying to keep it in.”

“I—I can’t,” Izuku gasps, but his hips are already tilting back, meeting the thrusts. His body is a traitor, singing a chorus of yes where his mind screams no.

“You can.” Katsuki’s voice holds a smile. “You will. I’ll make sure of it.” His thrusts become faster, harder, the plastic base slapping against Izuku’s soaked skin. “Such a good boy for me. Taking it so well.”

Izuku’s fingers claw at the sheets. The pleasure is a sharp, bright wire being pulled taut from his cunt to his throat. He’s panting, little broken sounds punched out with every inward drive of the toy.

Katsuki kisses his cheek, a dry, chaste press of lips. “That’s it. Let go. Give it to Daddy.”

The orgasm crests without warning, a sudden, violent rush that whites out Izuku’s vision. He cries out, a raw, shattered sound, as his body convulses, another gush of fluid spilling out around the toy with a hot, helpless rush.

Katsuki holds him through it, his arm a steel band across Izuku’s chest, his hand working the toy relentlessly through the pulsating contractions. “Good,” he breathes, his own voice rough now. “So good. Look at you.”

He finally stills the vibrator, leaving it buried. Izuku goes limp, boneless and spent, tears leaking silently from the corners of his eyes. Katsuki shifts behind him, his large hand splaying possessively over Izuku’s lower belly.

“See?” Katsuki whispers, his lips against Izuku’s ear. “No more doing it alone in the dark. Daddy’s here now.”

“My boy looked so beautiful,” Katsuki murmurs, his voice thick with something like awe. His hand presses down on Izuku’s lower belly, feeling the last internal tremors. “So fucking pretty when you squirt like that. Like an amazing fountain.”

He finally withdraws the vibrator with a slow, wet pull. The absence is profound, leaving Izuku feeling hollowed out and exposed. Katsuki flicks the switch off, the sudden silence ringing in the dark room, and sets the toy on the nightstand with a soft click.

“I’ll get you better ones,” he says, his tone practical, as if discussing school supplies. “Proper toys. For next time.”

Izuku can’t speak. He stares at the ceiling, tears drying in itchy tracks on his temples. His body is a foreign country, mapped and conquered.

“Well?” Katsuki prompts. His arm is still a heavy weight across Izuku’s chest. “Do you feel better? After coming so much.”

Izuku nods, his cheek rubbing against the soft cotton of his father’s shirt. “Yes, Daddy,” he whispers, the words a warm, sleepy exhale. He snuggles back into the solid wall of Katsuki’s chest, letting his body go completely limp. The heavy, safe weight of the arm across him, the steady heartbeat against his spine—he’s never felt so good. So protected. A quiet, shameful part of him already wants this again.

Katsuki’s hand strokes up and down his arm, a slow, rhythmic petting. “That’s my boy,” he murmurs. “All relaxed now. Told you I’d take care of it.”

“You did,” Izuku says, his voice muffled. He feels hollowed out and full at the same time, like all the frantic, buzzing energy has been siphoned away, leaving only a warm, liquid peace.

“Look at you,” Katsuki says, his tone holding a quiet wonder. He shifts slightly, his fingers tracing the damp, cooling skin of Izuku’s belly. “Soaked. My amazing little fountain.”

Izuku flushes, but the shame is a distant echo. The compliment, twisted as it is, sinks into him like a stone in a pond. He presses back harder, seeking more of that solid heat. “Was… was that okay?”

“Okay?” Katsuki lets out a soft, gruff laugh, his chest vibrating against Izuku’s back. “Baby, you came so hard you cried. It was perfect.” His hand slides lower, his fingertips just brushing the wet, sensitive curls between Izuku’s thighs. “This is what happens when you don’t hide from me. You get what you need.”

Izuku shivers. His body, traitorously, stirs again at the faint touch. “I wasn’t hiding.”

“You were.” Katsuki’s voice is matter-of-fact. “In here. In the dark. With a cheap piece of plastic.” He gestures toward the nightstand with his chin. “That ends now. You understand?”

“Yes.”

“Yes, what?”

Izuku swallows. “Yes, Daddy.”

“Good.” Katsuki’s arm tightens briefly, a possessive squeeze. “Then we’ll do it this way from now on. No more secrets. No more shame. You come to me when you need it.”

Izuku’s breath catches. “Just… come to you?”

“However you need to,” Katsuki says, his voice dropping to a low, intimate rumble right against Izuku’s ear. “Tell me. Show me. However it happens, I’ll handle it. That’s my job.” He presses a kiss to the crown of Izuku’s head. “Taking care of you.”

The words wrap around Izuku, a new kind of law. He closes his eyes, letting them sink in. The fear is still there, a cold little stone in his gut, but it’s outweighed by a devastating, grateful relief. He won’t have to be alone with it anymore. The want, the dreams, the wetness—it all has a place now. It belongs to his father.

“Okay,” Izuku whispers.

“Okay,” Katsuki echoes. He shifts, beginning to disentangle himself. “Get some sleep. I’ve got an early patrol.”

The loss of his warmth is immediate, a chill sweeping over Izuku’s skin. He turns onto his back, watching as Katsuki stands up from the bed. His father is a tall, broad silhouette against the dim light, rolling his shoulders. He picks up the vibrator from the nightstand.

“I’ll clean this,” Katsuki says, holding it up. “And like I said. I’ll get you better ones.” He looks down at Izuku, his red eyes glinting in the dark. “This was just the start, baby. We’re just getting started.”