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Yuuji has a new boyfriend. Cute, a little antisocial, obviously doesn’t like Sukuna.
It’s not like Yuuji hasn’t had boyfriends before, but he seems to like this one a lot more than his previous ones, shown by how often they’re together and how much Yuuji’s boyfriend is over at their house. Now, Sukuna doesn’t have a problem with them hanging out if they’re quiet (not like one of Yuuji’s exes, who always sounded like a wailing donkey and looked like they belonged in 2006), but it is a problem when Yuuji’s boyfriend comes storming downstairs and leaves without a word, slamming their front door shut.
“Megumi!” Yuuji shouts. “Come back, please!”
Sukuna snorts. Yuuji glares at him. “What’d you do?”
Yuuji glares at him harder. It isn’t intimidating at all; Sukuna has long gotten used to the expressions his twin makes when upset at him. “None of your business.”
“I live here,” Sukuna says, reclining in his seat, “and I’m your brother. So it is my business, actually.”
Yuuji huffs and pulls out his phone, probably to text Megumi. He makes a distressed sound and runs his hand through his hair. “I fucked up,” he mutters, blowing out a breath and scowling.
Sukuna pats his thigh. “Come tell nii-chan all about it.”
“Don’t call yourself that, you’re only three minutes older than me,” Yuuji says, but he sits next to Sukuna anyways. Sukuna pretends to read his book while Yuuji tries to gather his thoughts and feelings. “I think Megumi’s mad at me.”
“No shit.”
“You’re so mean to me,” Yuuji says, punching his shoulder. Sukuna barely flinches. “He… how do I put this. He was trying to initiate, I think. And I didn’t really want to, so I suggested doing something else and then he got all huffy, and then he was saying stuff like ‘do you even want to be with me’ and— I dunno. Yeah. Um. Wow.”
“Sounds like a bundle of joy.”
“He’s really nice, I swear! It’s just that. He keeps wanting to do it but I don’t… feel like I’m good enough to do that with him. Because, you know.” Sukuna raises an eyebrow so Yuuji continues. “I don’t.. have a lot of experience?”
Sukuna’s lips quiver. His shoulders shake. He tries to hold it in. He really, really does. He can’t help it when he bursts out laughing over how sad Yuuji looks, shoulders hunched in and pouting. He looks so miserable it’s hilarious. Yuuji scowls at him.
“You’re pathetic,” Sukuna says, still laughing. “Why don’t you just practice or something? That way you don’t have to embarrass yourself in front of your pretty little boyfriend again.”
“I don’t have anything to practise on,” Yuuji says, tucking his legs under himself. “I don’t wanna buy a toy either, that’s weird.”
“Aren’t you literally sucking and fucking another man?” Sukuna leans in and pokes Yuuji’s cheek with a leering grin. “Unless you’re the one getting fucked?”
“Shut up,” Yuuji spits, shoving Sukuna away. He just laughs. “I don’t. Ugh.”
Something flashes across Sukuna’s mind. It makes his heart jump into his throat and his belly burn bright. He grins. “You know, I’m here. Like literally right here. I can help you.”
Yuuji scrunches his face up. “No. You’re my brother. That’s weird.”
Sukuna shrugs. “It’s not like we’re having sex.” Not yet, at least. Sukuna would be more than willing to help his precious little brother out with things like that. “Besides, it’s only weird if you make it weird.” Yuuji still hesitates. “Do you want to get better or not, you little shit?”
“Hmm.” Yuuji squints. He eyes Sukuna up and down and pouts in further contemplation. “Mm… fine.”
It’s not like they haven’t seen each other naked before. They’ve grown up around each other, been through everything together: every loss and triumph, every first kiss and relationship, and now—
Yuuji’s hands tremble when they reach for Sukuna’s waistband. Sukuna had made him kneel on the floor in front of him so he could really understand what it was like. He’d probably done it before. Sukuna needs to make sure that he’ll be the only one his precious brother remembers, needs to carve out his place in his throat and the shape of him into his memory. Yuuji manages to tug Sukuna’s sweatpants down enough for his cock to bob out, barely hard.
He stares at his dick for an unnerving amount of time. He swallows audibly. Licks his lips. Opens his mouth. Closes it.
“Hurry up,” Sukuna says, arms over the back of the couch. “I’m gonna go soft at this rate.”
“Shut up,” Yuuji retorts, but he grabs hold of Sukuna’s cock and just. Holds it. His hand is warm and slightly calloused from his gym sessions, but it doesn’t do very much for Sukuna. “Um.”
“Do you know how to jerk off or not?” Sukuna snaps. Yuuji flinches, hand squeezing his dick slightly out of surprise. “I’m not surprised your boyfriend left if this is what you were doing with him.”
“That’s not it,” Yuuji says, giving Sukuna a singular stroke, long and clumsy. His hand is too tight and too dry and it doesn’t feel good in the slightest. Sukuna doesn’t even want to know how his poor boyfriend manages to stick around if this is what he has to deal with. “I’m just. I’m nervous, okay?”
“About what?” Sukuna holds Yuuji’s hand up to his mouth and spits in it, ignoring Yuuji’s whine of protest. He doesn’t care, takes Yuuji’s hand in his own and shows him how he likes it: wet, slightly loose, focused on the head. “You’re worried about nii-chan?”
“Stop,” Yuuji says. “Stop calling yourself that.”
Sukuna’s cock kicks in interest when Yuuji leans in, hovering over the tip. He exhales when Yuuji licks it, tastes the pre, rolling it around in his mouth. He does it a few more times, testing it out, seeing what Sukuna likes, what makes him react. He presses clumsy kisses along the bottom, carefully traces his tongue along the vein running up the side, blinking up at Sukuna before he rises up.
Sukuna hisses when he finally takes the whole thing into his mouth, teeth scraping along the bottom. Sukuna tugs him off with a sharp, “Watch your fucking teeth.”
“‘m sorry,” Yuuji gasps, not sounding at all sorry. He’s already back at it the second Sukuna lets his head go, drooling over Sukuna’s cock and making disgusting slurping noises whenever he comes back up for air. It’s horrendous, overly sloppy and Yuuji keeps gagging when he isn’t even halfway down Sukuna’s cock, and his teeth keep scraping the underside, but Sukuna can’t help but find himself so turned on by it that it’s almost embarrassing.
“You’re horrible at this,” Sukuna says, trying to ignore how breathless he sounds. Yuuji doesn’t need to know.
“I’m trying my best,” Yuuji says with a pout, lips swollen and shiny with spit. He’s palming himself through his sleep shorts, obscenely tented, a wet patch on the front of them. He’s already a mess. Sukuna’s almost proud when he dives back in without hesitation.
“You really think your boyfriend would get turned on by this?” Sukuna says, hand in Yuuji’s hair and holding himself back from forcing his entire cock down Yuuji’s throat, wondering if he’d be able to manage it like a champ, or if he’d gag and have to pull off. “You think he’d get turned on from all your slobbering and gagging and how you can’t even get half of your brother’s cock down?”
Yuuji’s throat spasms. His hips jerk before his entire body stills. Sukuna stifles a laugh. No, fuck that. He laughs at Yuuji’s flushed face, bright red from mortification.
“Shut up,” Yuuji says, but it’s useless. Sukuna’s already laughing at him and taking a photo of his pathetic mess, his own cock in the frame and everything. “Shut up, shut up, don’t laugh at me! Don’t tell him, please? Please, please don’t tell him!”
“Sure,” Sukuna says, fisting his cock lazily. “I won’t. If you finish me off.”
Yuuji pouts at him, spitting into his hand and using it to jerk Sukuna off slowly.
“You know,” Sukuna says, “I might let him know what a good boy you are. I’m sure he’d love to hear how well he takes nii-chan’s cock, yeah?”
“Nooo,” Yuuji whines. He holds Sukuna’s cock in his mouth, barely past the tip, strokes rough and awkward but just enough for Sukuna to finish inside his mouth, warm and waiting. Sukuna holds his mouth shut forcefully so Yuuji has no choice but to swallow. Sukuna pats his cheek when he does, murmuring a quiet, good boy.
Megumi comes back later. Yuuji apologises to him and asks if they can make up. Sukuna pretends to read his book but the only thing he can think about is Yuuji’s pathetic blow job and how he’s going to give his boyfriend the same treatment. If only he knew. The photo on his phone should be more than enough. Sukuna knows that Yuuji will be running back for more “practise” sooner rather than later.