pre-relationship, pro heroes izuku and katsuki getting stranded at inko’s place for whatever reason, and they end up sleeping in the same room together.
they havent slept in the same vicinity since the ua sleepaway training camps, and even though they’re super close now and stay over at each other’s places, they’ve always tried to sleep in separate rooms. (they both think it’s bc it’s the sensible way, and NOT because they’re avoiding the weird tension between them lately)
but this time, inko insisted that katsuki MUST set up in izuku’s room, and izuku’s all flustered, but that’s normal izuku.
middle of the night, Katsuki is staring at the ceiling of Izuku’s childhood bedroom, glow-in-the-dark All Might stars staring back at him. He hears Izuku’s mattress shift, and then suddenly Izuku is worming his way into Katsuki’s borrowed futon.
Thinking that Izuku is sleep walking, Katsuki moves to see Izuku’s face, only to see him turning away, flustered, eyes downcast.
“What’s this about?” Katsuki whispers, shifting to his side to give Izuku more space to move in.
“I’m cold.” Izuku replies simply and cocoons himself with what was supposed to be Katsuki’s blanket.
“You have a whole blanket and bed, nerd.”
“Yeah, but you’re warmer.”
Katsuki’s stomach flips. Is this Izuku deciding to finally break whatever it is between them, by initiating something first? Is this it? Is this my in? I can’t believe he beat me to it!
Katsuki gulps and says, “Come closer then,” while opening his arms under the blanket.
Izuku blinks up at him and eagerly closes the gap, wrapping his arms around Katsuki’s back, and leaning his ear against his chest.
Kacchan’s heartbeat is rapid, and Izuku almost asks if he is “okay” out of worry. But when he lifts up his head, he sees Katsuki’s soft eyes taking him in, and the words vanish from his mouth.
They stare at each other for a moment.
“Izuku,” Katsuki says.
“Yeah?”
“I’m gonna kiss you, bite me hard if you don’t want it.” And Katsuki leans in, pecks Izuku’s lips before pressing in for a proper lip lock.
Izuku’s eyes flutter and he lets Katsuki guide him. He licks and Izuku opens. His tongue explores and Izuku whines in response. He nips and Izuku bucks against Katsuki’s thigh.
“I like you.” Katsuki sighs into the corner of Izuku’s mouth.
“I like you.” This time underneath Izuku’s right ear.
“I want you so much,” Back into Izuku’s waiting mouth.
Katsuki embraces Izuku into him, and rolls himself under. He slides his hand down the side of Izuku’s torso to his hips, and grins at the way Izuku shivers.
They pull away heaving. Izuku straddles Katsuki’s waist, taking in his debauched face and kiss bitten lips.
“Kacchan…” Izuku rolls his hips a little, just to see Katsuki’s breath hitch.
“Mm-yeah?” Breathless. He is so breathless and beautiful as he looks up at him.
Before Izuku can chicken out, he leans back down for another kiss, “We have to be quiet, okay?”
Katsuki nods dazedly, “ ‘kay.”
They make quick work to take their sleep shorts off (as much as they can at least without separating their lips), gathering both of their arousals into their intertwined hands.
Izuku gasps into Katsuki’s mouth as he begins to thrust into their fists, “I like…you too—mmh!”
Katsuki undulates his hips to meet Izuku’s movements. The slick friction of both their members rutting against each other, sends a satisfying buzz at the back of Katsuki’s skull. He groans a bit too loud and Izuku replies with a wavering “Shh. Kacchan quiet~nnh.”
As a tease, Katsuki takes his thumb and massages the tip of Izuku’s head. Which only causes Izuku to convulse and spill into their fists with a whine that Katsuki can never forget. “Did that feel good, hm?” Katsuki smugly asks, as he chases his own orgasm.
He covers Izuku’s fist with his own hand and tightens his grip against their dicks. He then begins pounding into the hole with vigor, drinking in Izuku’s whimpers from the sensitivity.
“That feel good, Izuku?” Katsuki kisses and kisses like a madman, until Izuku finally replies with a desperate yes, and a plea to keep going faster.
When Katsuki cums, Izuku does so for a second time. They look into each other’s eyes, basking in the haze, musk, and afterglow.
“That was so good.” Izuku croaks out, which makes Katsuki laugh.
“We can keep doing it…” Katsuki sits up to grab tissue paper off of Izuku’s night stand.
“I sure hope so,” Izuku mumbles he stares down at the gentle way Katsuki wipes the spend off his hands. The intimacy makes Izuku’s heart balloon, despite how gross it is. “God, I hope this isn’t just a one time thing, Kacchan. Please tell me this isn’t.”
“What the hell do you think I meant by ‘I like you’ you damn nerd? You’re mine now.” Katsuki scoffs, shoots the napkins into Izuku’s trash bin, and pulls them both back down under the covers. “That means dates with me, kissing with me, and fucking me or fucking you. Whatever you want, I’m down for both.”
Izuku nuzzles into Katsuki’s neck happily, “My boyfriend. My boyfriend. My boyfriend.”
Inko peeks into the room the following morning, heart melting at seeing the two embracing under the same futon. Then her face flames when he sees the discarded shorts next to them, and leaves the house with such speed towards the Bakugo home.