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His little sister has mastered the art of calming him down to the point it’s kind of embarrassing.
All it takes is her taking his face into her hands, kissing his forehead, and promising him that when they get home, they can cuddle in her bed. For all the people in school that fear Sukuna, cowering back and excusing themselves when he approaches, he’s devastatingly susceptible to falling for her charm.
It doesn’t matter how fucking pissed off he is, or how bloodthirsty. It doesn’t matter how nice it feels to beat some annoying fuck’s face in until he’s seizing, nor does it matter how satisfying it is to succumb to rage and blindly hurt everything that can hurt. Being pressed against her soft body and held in her strong arms, inhaling her sweet scent, is more than enough incentive to stop.
It’s a win-win situation, honestly. Yuuji only ever offers it when he’s beyond pissed that he ends up hurting someone. He gets to shed some blood and remind these fuckers who they’re messing with, and then he gets to have his knuckles cleaned and patched up by his cute sister who then holds him throughout the entire night.
She’s a weakness that people know of, foolishly threatening her to rile up Sukuna—and it fucking works, but never in their favor. If anyone ever says Itadori, the next name better not start with a Y or he’s knocking their teeth out before they can finish tainting her name with their filthy mouths.
His sister is sickeningly kind, too kind for Sukuna’s bullshit, really, but Sukuna is more than aware of how her constant lectures never include pleas for him to stop what he’s doing. It includes more of how he needs to look out for himself before someone ends up killing him. He always reassures that the other person will be dead before that possibility is even conjured.
It’s not like she ever gets angry when she walks out into the school halls to discover that he’s in yet another fight, either. Or whenever she’s called into the office to come get him because they know she’s the only person who can deal with him.
He’s starting to think she looks forward to having an excuse to hold him. He won’t bring it up nor will he complain. He couldn’t have asked for a better little sister. She doesn’t give a shit that Sukuna is seventeen and two years older than her, it has never stopped her from babying him. And Sukuna loves to be babied.
He got into an argument with one of his fuckass teachers today, which resulted in one of his violent outbursts before he stormed out of the class, agitated. The ability to graduate is looking a little grim, Sukuna can’t lie. So, in order to keep from bashing some adult’s head in, he simply went to Yuuji’s classroom, ignored all the bewildered glances, and beckoned her over.
She threw an apologetic look at her own teacher, grabbed her bag, and followed him out of the school, grabbing his hand and pulling him closer to her. In his car, he got an earful about needing to take school more seriously, but he also got a sweet caress of his jaw and a saccharine gaze of pure affection in warm brown eyes.
Sometimes, Sukuna finds himself wanting to be better just for her.
For the Yuuji that’s currently holding him in a position they’re all too accustomed with. They’re in her big canopy bed that’s filled with a diabolical amount of pinkish pillows, and she has a protective arm around his shoulders as he’s comfortably tucked into her side, his cheek pressing against her boob. It’s a guaranteed position to soothe him to sleep, especially with her hand caressing his shoulder absentmindedly.
Instead of sleeping, though, he’s too aware of her soft tit against his face. It’s nothing he’s not used to at this point, never having thought much of them beyond what a girl with big tits’ brother would normally think, but maybe it’s the thin white tank top she’s wearing with no bra. Her nipples are hard, poking through the fabric right in front of Sukuna’s eyes, and he can’t stop looking.
The fabric is a little see-through, too, and he can see that her nipples are brown and puffy. Sukuna shifts so his growing erection doesn’t end up poking her, a tell-tale sign of his insanely rotten brain. But how can he stop thinking about it when she’s so soft against his face, the flesh giving with each little movement of his head? He wants to see them bare, he wants to bury his face in between them and breathe in her sweat, and his arousal only surges when he thinks of sucking on them, eager to hear the cute noises she’d make.
She’d look and sound so pretty, her blush always reaching every bit of her face. Sukuna sucks in a breath, trying to ignore the heat growing within his abdomen. He had always liked having something in his mouth, constantly biting Yuuji growing up, and it’d be incredibly comforting to suck on her tits.
His cock twitches. He squeezes his eyes shut, his ears burning. No fucking way he’s getting this hard over the thought of his little sister’s tits. He’s sure Yuuji wouldn’t be too pleased to know that. Yuuji’s not paying him an ounce of real attention, though.
She’s got her headphones in, her other arm holding her phone above her face, watching Hunter x Hunter for the millionth fucking time. And she never skips openings either, so he knows she’s heard that damn song in full well over 500 times. Whenever she’s engrossed in something, she’s really engrossed.
It would be so easy to pull her shirt down a little bit and get a peek. He wonders if she’d feel the air on her nipple, or if she’d feel her shirt move. He could lie and say it was an accident if she asks. She’d forgive him.
He’s purely thinking with his dick when he gently pinches a folded over section of her shirt on her stomach, pulling down slowly with his eyes fixed on her breasts. He bites his lip when he sees the top of her areola and nearly groans when a little more pulling has her entire nipple peeking out, begging to be bitten and sucked.
He bets if she had milk it’d be sweet. It’s that single thought that has all rational action fleeing; he had only meant to look, but it’s the most natural movement in the world to extend his head a little, part his lips and take her nipple into his mouth, moaning at the feel of it on his tongue.
He gets to enjoy the sensation for all of one millisecond before Yuuji gasps loud as fuck and suddenly, Sukuna’s head is ripped off her tit, her grip on his hair extremely painful. “What the fuck are you doing?”
There’s no talking himself out of this one, but he can barely be concerned about that when he catches sight of her nipple glistening with his spit. He inhales deeply; he fucking needs her tits in his mouth more than he’s needed anything in his entire life. His cock is aching with the need, and for once in his life, he’s not above begging.
“Yuuji, please,” he breathes out, sounding pathetic and ridiculous in his own ears. “Please, I won’t do anything else, I promise, but please.”
She’s bright red. So pretty. She doesn’t look angry, but more so bewildered. “Please what?”
She’s going to make him say it? “In my mouth,” he says dumbly, starting to feel increasingly more embarrassed. He hopes he didn’t ruin anything. “It’s not sexual,” he lies. “It’s just…soothing,” he doesn’t lie.
He watches her face and all the different expressions that cross it are unreadable in his arousal-induced addled brain. He tries his best not to look at her nipple that’s still exposed, her pretty brown nipple that needs to be licked. It’d feel so good for her, too.
Yuuji sighs. “Fine. Don’t do anything weird.”
Sukuna nearly dies from his elated relief, his cock already starting to leak precome—he must be pent up. He can’t remember the last time he’s jerked off if he’s this turned on to suck his sister’s juicy tits. Don’t do anything weird. Sukuna will try his damned hardest.
And it’s extremely hard when Yuuji briefly sits up to take her entire shirt off, putting her gorgeous tits on full display. Sukuna will be jerking off to the memory forever. She pulls Sukuna back into her side and doesn’t complain when his hand grabs her other tit, squeezing as he happily latches on to her nearest nipple with a groan, delighted to hear her soft little gasp.
He expected Yuuji to go back to her phone, not being involved in Sukuna’s indulgence at all, but instead, she holds the back of his head, fingers tangling in his short hair. The gentle caress makes his entire body hot as he sucks rhythmically like he can pull some milk out of her, occasionally flicking his tongue just to hear her moan quietly.
He wonders if she’s wet, if it’s as good for her as it is for him. The thought makes him want to grind his cock into her so bad, but he resists, no matter how much his cock is screaming for relief. He hasn’t been this hard in forever.
Yuuji giggles. “You look like a baby like this.”
He glances up at her smiling face, her blush the brightest he’s ever seen it, and he wants to kiss her.
“I guess that makes me your mommy. It’d be accurate, huh? Since you’re my baby. Mommy’s baby,” she laughs, scratching his scalp.
Sukuna moans, his arousal intensifying by a thousand, his cock jolting incessantly in his pants. Mommy’s baby. Yuuji calls him her baby all the time, but never has she called herself mommy, his mommy. She’s joking, but Sukuna’s mind is reeling. Yuuji would be such a good mommy, she is such a good mommy to him.
He knows his cock is probably forming a wet spot in his briefs right now, but he can’t help it. Her tits are so soft in his grasp and mouth that he wants to squish his face in them until he suffocates and dies. He wants her to caress his hair and call him her baby all throughout it.
“You’d be such a good baby,” she says, her voice quiet, nearly a whisper. “So perfect for mommy.”
Sukuna shudders, heated pleasure radiating from his crotch as if he was being touched directly. It’s like she’s trying to make him come undone.
“You look so cute and sweet, Suku. I just want to eat you,” she coos, shifting a little so that her tit presses even further into his face. Sukuna might pass out. He can’t think properly. Every one of his senses is filled with nothing but his mommy; how she feels, how she tastes, how she smells, how she sounds.
He can’t believe one girl could be so insanely perfect.
She moans when he nips her nipple, her fingers twitching hard in his hair for a moment. “Be gentler for mommy.”
He mumbles an intelligible, “Sorry, mommy,” against her breast, and even though she could hardly hear him, calling her by mommy feels entirely too natural. She’s pampered him far more than their actual mother ever has. She doesn’t quit talking either, her little whispers curling around his brain pleasantly and sending him closer to what he fears will be an untouched orgasm.
With the way his cock is throbbing, feeling so fucking good despite being met with absolutely nothing, it’s possible.
“You know, Suku, I love being your mommy. I love having you in my arms and rocking you until you fall asleep. I love kissing your forehead until you calm down. You’re the most perfect boy,” she says, leaning down to kiss the top of his head. He wishes it was his lips. He wonders if he’s been good enough will his mommy give him a kiss.
He’s panting uncontrollably now, breathing rapidly through his nose as he tries to calm himself down to no avail. There’s no calming the intense lust infiltrating every single part of his brain while he’s still in her arms, sucking and licking on her nipples, helpless to the fantasies of sweet milk.
Would she praise him if he drank it fast enough? Would she kiss him afterwards to taste her own sweetness? Would it put him right to sleep and leave his stomach satiated and full?
“Are you feeling good for mommy?” she whispers, and his body shudders so hard, hot sensation in his cock far stronger than it has any right to be, to the point he thinks he’s about to come. He pulls off her tit, gasping. He has half the mind to try to salvage this before he makes a mess in his pants and weirds her out.
“Yuuji,” he gasps, her name feeling wrong in his mouth. “Stop talking. Please.”
“Why?” she asks with a pout. So cute. “Are you done?”
No, he wants more! “No, I…” He wonders how he must look. His lips feel wet and his face is on fire. His cock is straining against his pants painfully. If Yuuji wasn’t concerned for him before today, she must be now. He’s a freak.
She lovingly cups his jaw, leaning in a little. “Was my baby about to come?”
Sukuna’s heart stops for a moment, all feeling lost except the agonizing pressure in his dick. He can’t respond to that, not when the answer is an obvious yes. All she has to do is glance down and she can see just how much of an effect she has on him.
“It’s okay. You can tell mommy,” she coos, caressing his cheek with her thumb.
All he can do is nod.
“Use your words for me.”
“Yes, mommy,” he says, and his own voice feels foreign to him. Desperate. Needy.
She grins, presses a kiss to his nose, and says, “Then mommy will make her baby come.”
That’s almost enough to make him come right there. All he musters is a whiny moan, barely comprehending when Yuuji props herself up a little more above him, pressing her nipple into his lips. He latches on instantly, his mouth blissfully accustomed to the sucking. One hand resumes in his hair and her other reaches over, pushing his waistband over his flushed and leaking cock.
She wastes no time, spitting into her hand and grabbing it, Sukuna immediately bucking into her warm touch. His eyes roll back into his head with her first stroke, his breath caught painfully in his throat as the pleasure increases tenfold. She holds him in a nice, tight grip, twisting her hand quickly with intent.
“You’re so good for me, Sukuna. So good for mommy.”
He moans nonstop against her skin, squirming like a little bitch under her touch. In his head, he’s crying out mommy, mommy, mommy, and he knows if his mouth was free, he’d be damn near yelling it.
“Mommy’s baby is so big,” she says, her soft voice starting to sound hoarse, like he’s affecting her as much as she’s affecting him. And that thought feels way too good. “You’re always so warm. I know you’ll come so well for me.”
She quickens her hand, making sure to bring her palm over his wet tip, and she lets Sukuna thrust wildly into her grip, chasing his release that’s so fucking close he worries it might make him blackout. He’s straight up whimpering now, more overwhelmed than he’s ever been with anything, and all he can do is succumb to her.
“Come for mommy, Sukuna,” she says. “Come for me.”
Ever so quick to obey her, he does, violently shuddering in her arms as his cock pulses hard and spits all over her hand that still moves. It’s the hardest he’s ever come, the white-hot pleasure hitting every point in his body to the point he feels like he’s vibrating, on a different plane. Yuuji praises him through it, whispering sweet words of, “Good boy, you’re so good, Suku, mommy’s perfect little boy.”
Her tit slips out of his mouth when she shifts downward so that they’re face to face, breathing in each other’s air. He looks at her through half-lidded eyes, fighting for his life to keep them open. The aftershocks of his orgasm are still wracking through him, and he doesn’t sound like himself when he whines, “Mommy.”
She frowns, one of her sympathetic, loving frowns, and then she kisses him, effectively killing him again. Her kiss is gentle and soft, filled with so much love Sukuna thinks he’ll die, and then she pulls him into an embrace that only makes him feel incredibly raw and vulnerable.
He must whine again, past the point of shame, just wanting to be held and loved by his mommy, because she pets his hair, cooing, “Shh, shh, mommy’s got you, baby.”
All it takes is a few more minutes of her soft voice caressing his ears, her warm embrace Sukuna’s personal solace, before he’s knocked the hell out.