Bakugo has an oral fixtation

 Bakugo has an oral fixation and gets all grumpy when he hasn't been able to shove his boyfriend's cock down his throat. It felt like weeks had passed since he'd done it, but it had only been three days, and Bakugo hated it. Bakugo had been more short-tempered than usual, taking out his rage on low-level villains and then snapping at the civilians he helped because he was 'just doing his damn job.' they thanked him for helping them anyway. Deku, of course, noticed Bakugo's usually short temper becoming shorter as the days passed; it was easy for Deku to tell when Bakugo's demeanour changed since he had been studying Kacchan since they were kids. When both heroes got home and slipped off their hero gear, Deku kept his gaze on his boyfriend. He noticed how Kacchan's eyebrows stayed furrowed and how he gritted his teeth unconsciously as he sat on the couch. Deku could tell he wasn't actually paying attention to the tv; Kacchan was stuck in his mind, and Deku knew it wasn't a place Kacchan liked to be in for too long. Sighing. Deku walked over to his frustrated boyfriend, who didn't even notice him until he used his calloused thumb to smooth out Kacchan's furrowed temple. "Hi, sweetheart," Izuku greeted. Kacchan's eyes sparkled when they met his green orbs; his crimson eyes lit up with happiness at the sight of his boyfriend. Izuku couldn't help but coo at him internally, bringing a hand down to Kacchan's waist and rubbing soft circles on it.

"Zuku..." the blond whined, tugging at Izuku's heartstrings. He sounded so needy. "Yes, Kacchan?" Izuku asked, causing Bakugo to huff at the fact that his boyfriend didn't instantly know what he needed. "Kacchan, I can't read your mind, sweetheart; you have to use your words and communicate what's going through that little mind of yours." Bakugo stuck his bottom lip out in a pout. Why couldn't his dumb boyfriend figure out he just wanted his cock shoved inside his mouth?! Bakugo didn't like using his words, so instead, he showed Deku what he needed by getting on his knees in front of him and nuzzling his boyfriend's clothed cock with his cheek. Izuku couldn't help the shiver that came down his spine at the shameless action. He put his hand on his boyfriend's head, running through his spikey hair. "Is that it, pup? You just wanted my cock in your mouth?"
Deku's voice had dropped a few octaves by this point, forcing Katsuki to suppress a slutty whine due to how turned Deku's voice made him. Fuck his voice, kink. "Please, Zuku..." Bakugo breathed a shaky breath when Izuku stood up from the couch to lower his trousers to the floor along with his underwear, kicking them off before sitting back down on the sofa with his lower half exposed. Bakugo's mouth watered when he locked eyes with his boyfriend's semi-hard cock. "Go on, puppy; nothing's stopping you." And that's how Bakugo ended up asleep with his boyfriend's cock deep in his throat while also deep in subspace.

Izuku spent the hours scrolling through his phone, letting his boyfriend warm his cock with his mouth until he figured enough time had gone by. He ran his fingers through the blond's hair, speaking to him in the sweetest voice to not startle him when he awoke. Because Bakugo's legs had been in one position for so long that when his sleepy eyes fluttered open, Bakugo hissed slightly at the pain of his muscles reviving, prompting Izuku to spoil him with sweet encouraging words. Izuku gently coaxed him off his cock and helped him up. "It's okay, Kacchan. You did so well for me, puppy. Warmed me up so nicely, like the good boy you are. Kacchan's so good at what he does." Izuku pulled the spacey boy onto his lap, peppering kisses all over his face and praising him to help ground him. It's safe to say that the next day when Bakugo woke up, he was in the best mood yet, so much so that some of his friends wondered what had gotten into him. The answer was Deku's cock.