#dkbk #miritama #nsfw #r18

deku knows that what he’s doing is wrong. like, *really* wrong; the kind of wrong that won’t be easily forgiven, not even by someone as good-natured as mirio.

deku blew his chance to do the *right* thing about...10 minutes ago.

10 minutes ago, he should have left the gym after solo training. 10 minutes ago, he should have just kept walking after hearing a muffled groan coming from one of the private training rooms.

10 minutes ago, he should have told mirio and tamaki that they weren’t alone.

even when it’s the right thing to do, deku sometimes has trouble doing what he *should.* stubbornness plus fanboy thirst for new info about his favorite heroes means he is known to make some questionable decisions.

that’s why, 11 minutes ago, he became a voyeur.

there are a million reasons why deku chooses to stay and watch mirio and tamaki instead of alerting them to his presence, but as usual, his main motivation is rooted in curiosity. he’s curious about so much...

like, what is mirio doing to make tamaki sound like *that*?

not literally, of course, deku knows exactly what mirio is doing, and the evidence of just how *well* he’s doing it is all over tamaki’s flushed face. his dark eyes on mirio, wet mouth open as he...whimpers?

deku’s not sure what to call it, but it’s making him hard as fuck.

deku prays that they won’t notice him. he needs to know *how* mirio is eliciting those sinful sounds from tamaki, a boy who can’t even speak to his underclassmen without mumbling and blushing.

if mirio can get *tamaki* to make noises like that, then it’s possible for deku, too.

deku blushes as mirio and tamaki start making out. his violation of their privacy now feels even worse, as if watching mirio suck on tamaki’s bottom lip is somehow more invasive than seeing tamaki’s long, beautiful legs spread wide as mirio holds him down and fucks him.

maybe it feels like that because he and kacchan never, *ever* kiss. kacchan never makes noises like tamaki, either, not even when deku is fucking him for all he’s worth. deku can tell kacchan is forcing himself to be as quiet as possible, especially when deku makes him cum.

deku almost cums in his pants when he hears tamaki moan *into* mirio’s mouth. mirio must have a similar reaction because he rewards tamaki by bucking his hips harder and faster until he can no longer hold his head up to kiss mirio.

all tamaki can do is lie there and take it.

jealousy competes with arousal as deku watches mirio brush tamaki’s damp hair off of his forehead and kiss the sweat from his skin. he imagines kissing kacchan’s face and mouth as he slowly fucks into him.

what a fantasy: kacchan moaning like tamaki while deku holds him close.

for mirio and tamaki, this is clearly more than just fucking. deku’s never even had the chance to kiss kacchan during sex because kacchan makes deku fuck him from behind, always.

deku can only tell how good it feels by the way kacchan’s hands leave scorch marks on his sheets.

mirio’s voice breaks deku’s reverie. it’s so choked with lust that deku knows it’s going to be hard to interact with mirio without blushing after this.

“tamaki, ah, you’re so tight. you’re so good at taking me. you’re gonna make me cum.”

tamaki moans and arches into mirio.

“you feel so good, tamaki. you’re so beautiful like this.”

deku notes how tamaki responds to mirio’s praise. although he’s never had a conversation with tamaki that lasted longer than it took for mirio to return from the bathroom, deku knows he’s about to watch tamaki cum.

tamaki is panting and whimpering and digging his nails into mirio’s wide shoulders as mirio fucks him relentlessly, the lewd sound of skin on skin filling the room.

mirio leans up a little so that he can reach between them and start stroking tamaki’s cock as he fucks him.

“mirio...’m gonna...” fuck, tamaki sounds absolutely wrecked.

“yes, cum for me, ah, tamaki.”

tamaki moans as he cums. by the way mirio is pounding him, he must be close, too. deku notices how hard mirio is squeezing tamaki’s hips and sees purple bruises bloom on his pale skin.

tamaki *let* mirio leave marks on him, marks that would remind tamaki of how mirio fucked him tonight.

deku wants to leave marks, too. he wants to make kacchan whine with how good deku makes him feel. he wants to fuck kacchan from the front and kiss him.

“i love you, tamaki.”

but most of all, deku wants to tell kacchan he loves him.

“i love you too, mirio.”

and he wants kacchan to say it back.

deku thinks that may be the key to everything he wants.