KINKTOBER DAY 1: Lingerie/ Pet Play
Bkdk where Katsuki starts having sexual dreams about Deku that involve numerous nicknames. It's whatever, he ignores it, until... He has these dreams so frequently that he starts accidentally calling Deku by the nicknames /out loud/.+

The first time it happens, he, his friends, and Deku are all in the kitchen. Deku's sorting out the cupboards, organising Katsuki's spices for him (he insisted, and Katsuki isn't going to say no to something that's actually useful), whilst his friends loiter about him. He's set +

the pan to simmer, ready to add the additional seasoning, but when he reaches for the salt first, it isn't there. Deku must have put it in with his spices, so Katsuki tuts and says, "Deku, pass the salt."
"Oh yeah, of course!" Deku chirps, reaching for the salt.
"Thanks, baby."+

Deku stumbles and almost falls off the counter he's perched on below the cupboard as the room goes silent.
And then:
"Dude, did you just call Midoriya… /baby/?"
Katsuki's eyes widen. He said that out loud. In real life. He pinches himself. Yeah, /definitely/ real life. Oh fuck.+

"T-The hell I did!" Katsuki stumbles over his words, blushing bright red. "/Baka/, I said baka!"
"Hmm, I don't know, Bakugou, sounded like baby from where I'm sat, and I'm literally right next to you," Sero muses.
"He totally did! He called Midoriya /baby/!" Mina yells, bursting+

into laughter. Katsuki brandishes his spoon at Mina, his cheeks burning.
"You're all fucking idiots, I called him baka!" Katsuki insists desperately, whirling around to where Deku looks like he's about to faint. "Tell them I said baka!"
"K-Kacchan called me baby," Izuku murmurs +

absentmindedly, utterly dazed. Fuck, that's no help.
"It's okay, dude, these things happen," Kirishima tries to reassure. "The number of times I've called a teacher my parent... It's no big deal!"
"Sounds like a Freudian slip to me," Kaminari teases, waggling his eyebrows. +

"How the hell do you even know what a Freudian slip /is/?" Katsuki retorts. Kaminari waggles his eyebrows even more, pointing at him with a shit eating grin.
"You're changing the subject!" he exclaims. "Which means you /did/ call Midoriya baby! Yo, that's /wild/."
"Whatever!" +

Katsuki huffs. "I meant to say baka! Like I'd /ever/ call Deku /baby/. 'S not fucking possible."
He misses the way Deku's expression falls a little, but little does Deku know that he /would/ call him baby in a heartbeat, and in his dreams that night, that's exactly what he's +

imagining, Deku a writhing, whimpering mess underneath him as he ploughs his ass into the bed. He pants over Deku and groans, "Fuck, you're so tight for me, baby. Mm, I'm gonna fill you up so much, I'm gonna pound you into the mattress until everyone knows you're mine, darling."+

He wakes up hard, as he has been for months now. God, it's like a plague, a plague where Deku fills his mind with inappropriate thoughts and desires and feelings he didn't even know he had. But he'd seen the way Deku had reacted to the pet name yesterday. He knows that Deku's +

never going to want him the way he wants him. But that doesn't stop his mind from slipping up yet /again/ a few days later, when he thinks that Deku's finally got over the embarrassing incident in the kitchen. Deku's in his room, studying with him, and usually, they're pretty +

equally matched in terms of intellect (as long as that's taken Katsuki to admit), but for someone reason, it seems that Deku is stressing all too much about the upcoming English exam. When Katsuki asks him what's up in as many words, Deku breaks down completely, burying his face+

in his arms as he gasps out, "There are so many /expectations/ on me for this, Kacchan! All Might's fluent in English, he spent ages in America, and I'm not as far as I should be! He was a level above me at this age, what if I don't make it, what if everyone hates me because my +

English is awful, what if-"
Katsuki's moves over to crouch next to Deku, a hand on his shoulder as he says:
"Darling, chill, you're one of the best in the class. And you're /you/. People ain't gonna love you for being a copy of All Might, they'll love you for your damn self." +

Deku blinks up at him, and Katsuki thinks he might have gotten through to him, but Deku shatters his confidence with one sentence:
"Kacchan, did you just... call me darling?"
Jesus fucking /damnit/. Deku's /just/ gotten over the last accident, and now this? He hates his mouth. +

"I called you Deku, the hell you on about?" Katsuki defends, hoping Deku doesn't notice the way he swallows nervously.
"O-Oh," Deku says, shoulders dropping. "Haha, I must be more stressed than I realised."
Wait, why did his shoulders drop? Katsuki's confused. The last time, +

Deku had seemed mortified over being called baby. So why does he seem to be disappointed now?
Maybe he likes darling and not baby? Or maybe he was /surprised/ and not mortified?
Had this been the first term, Katsuki would never have just /asked/, but he knows better now, so he +

asks, "Oi. Do you like pet names?"
Deku blushes bright red, sitting up straight. /Oh/. That's a yes. Katsuki's feeling bold now, so bold he might even ask what /else/ Deku likes (...whether he likes /Katsuki/), but then Deku speaks up.
"I-I like it when my friends are +

affectionate with me! It makes me feel comfortable. L-Like I'll have super long hugs with Todoroki, o-or I'll sleep against Uraraka's shoulder, that kind of thing! A-And you're one of my oldest friends, so pet names feel good! U-Uh, I-I mean in a platonic way. N-Nothing more of +

course, haha!"
Katsuki's heart drops. Right. Of course. The fact that Deku's letting him use pet names at all is something, right? It's a right he abuses as much as he can, calling Deku baby and sweetheart and honey and darling and every stupid cheesy thing that comes to mind. +

The only downside is the fact that the dreams only get that much more intense, dream Deku being fucked against every surface of UA as Katsuki croons, "Mmm, such a /good/ slut, aren't you, baby?" and "Fuck, I love watching your ass jiggle as I pound you, /sweetheart/" and "Fu-ck +

I'm gonna come down your throat, darling, /fuck/," and so on. Katsuki thanks the stars that he hasn't accidentally called him anything explicitly /sexual/ outside of his dreams. He'd die if he had to explain himself to Deku. Knowing that he's safe in a small set of pet names +

brings him peace.
But maybe he's spoken too soon, because he /does/ slip up, during a one-on-one training session. The fight is getting intense, the two of them grappling at each other fiercely because they can't use their Quirks. Deku looks /hot as fuck/ as he grabs at Katsuki.+

(You know what, fuck you Tweet limit, I'm going to go have dinner and watch some BNHA with my flatmate. How's that for driving me away with your cockblocking limits? The smut is coming real soon, I promise. I'm so excited to be writing this!)