Archive of Our Own ^beta

”Nii-san?”

Sero Hanta whirls around in his chair to look up at you by the doorframe. Your big brother moved out years ago but your mother has kept his room almost intact; she even made him buy all new furniture rather than letting him bring the ones from his childhood bedroom when he got his first apartment.

“Yer a big shot hero now, Hanta! Let this room stay your home!”

It’s almost comical to watch the adult man, with his beard and burly grown-up body hang out in a room decorated by a kid.

“What’s up, runt?”

You pout at his nickname. He’s used it ever since you were born just because you’re the youngest, but you’re not even that much younger than him, so it’s unfair.

His laptop is open on the messy and dusty desk. From what you can see he’s filling out boring paperwork. Everyone’s home for your cousin’s big wedding this weekend, but you’re not surprised that a Pro Hero like him had to bring work with him, too.

Everyone else is at your aunt’s house right now to help with preparations for Sunday, but you begged your mother to let you stay home with your brother who had to work. Your older sister had rolled her eyes and convinced your mother for you, “Ma’, c’mon, he’s never home anymore – let her spend some time with her big idol. I’ll fold her portion of napkins.”

You bite your lower lip, “’ve got a boyfriend.”

Sero’s eyes fly open and he sits up straighter in his chair, “woah! Are you even old enough to date?” he jokes, waving his arm to get you into his bedroom and spill the tea like always. The news would be happier if not for your problem, which is the reason you begged to stay home with him. He’s the only one you trust with this.

“C’mon Nii-san, I’m in high school already. Everyone’s dating.” You flop down onto his bed and cross your legs under you, “that’s kinda my issue.”

Your brother rotates his desk chair and raises a brow, “issue? Is he a bad boy? Want me to beat him up?” Sero almost jumps out of his chair, “are you bringing him to the wedding?”

You laugh at his eagerness before you raise your arms to calm him down, “no, no, relax,” you sigh and look at the floor, “haven’t told father yet. Not even Ma’ knows.”

He sucks in a breath through his teeth and you can see pride overflowing despite his best efforts at holding it back, “am I the first to know?”

You shake your head, “Nee-san knows.”

He punches the air, “dammit.”

You snort, “Nii-san, please, be serious.”

Your brother snorts back at you mockingly, “that’s hard, man! My little wittle baby angel getting a boyfriend before college? You’re breaking my heart! ‘m just coping with humor!”

You roll your eyes at him, waiting for him to end the theatrics. He sighs when he’s done mock-crying, “is he good to you, at least? He’s not making you do anything you don’t like, right?”

You groan, “that’s my problem. He’s very good to me and I kinda… I kinda lied to him.”

The silence is deafening. You hide your face in your hands before you confess your deepest, darkest secret, “I told him I had experience.”

You hope your brother gets it. But when you can’t even hear his breathing, you fear he might’ve vanished completely. You peak up through your fingers, “experience?” he asks when he catches your eye. You yelp and hide again, embarrassment making your heart race faster and your face feel sweaty, “he’s a transfer student, so I lied and said I’d already dated a few and… and that I’ve already had sex.”

If the silence felt heavy before, it’s crushing you now. You shake off any humiliation before you decide to raise your head and face him since you need his help to solve this, “and he invited me over this Tuesday… saying his parents won’t be home and… insinuating … you know…”

Your brother plays dead. His head has fallen back over the backrest of the chair, tongue lolling out. You decide to continue, “we’ve only kissed on the bed! And he said he’ll be in my care! I can’t back out now!”

Your brother groans. It’s long and loud and dramatic before he drags his hands over his face. You swallow as you follow his elbows’ movements before he manages to lift his head and look at you. He’s dead serious as he chokes out, “why’d you lie about that?”

You grimace at his stupid question, “everyone lies about that!”

He shakes his head while rubbing his eyes and you’re reminded of that picture of Hayao Miyazaki that circles the internet as an exhausted reaction. You almost laugh but you know this isn’t the time and bite your underlip instead. “So he’s a virgin and thinks that you’re experienced and that you’ll pop his cherry… or?”

You squeak as he looks you dead in the eye. You can do nothing but nod, “yeah! Do I tell him the truth? What do I do?”

Your brother sits up in his chair and shakes his head, all sober and done with the humor coping, “well, do you like him?”

“Yes! I l-love him!”

Your brother sighs deeply, “then you can definitely never tell him. Oh angel,” he gets up from the chair to the bed and sits down next to you, “that’s some real mess you’ve gotten yourself into.”

You groan, “I know! Maybe I could… Nii-san, can I order… something… to your place? I can practice this weekend! You can pick it up tomorrow, right? I’ll go with you on the subway.”

“Oh, a guy can definitely tell if you’ve just used a toy. He’ll leave you.” your brother looks at you like he’s sorry for you and it makes heat burn in your face, frustration bubbling up within you before you slump with a sigh, “then what do I do?”

Sero pets your shoulder, “did you tell anyone else?”

You shake your head, “no! My friends would never let me live it down and… I don’t know… you’re the only one I dared tell in the family. Please, Nii-san, I don’t want to lose him.”

Your eyes get misty with tears, “he’s the most popular in our year and he chose me! He’s perfect! He’s really funny and kind and I don’t want to ruin anything between us…”

Your brother coos at you as he pulls you into a hug, comforting you exactly how you need him to. Your sisters would make fun of you and scold you, but you knew your brother would understand. You knew he’d be there for you. Warmth and security washes over you as relief makes you slump in his grasp for a moment before determination takes its place.

You clutch at his shirt, “Nii-san, please, I’ll do anything to keep him.”

Your brother squeezes your smaller body into his, “yeah? He’s that important?”

You nod into his neck as you nuzzle closer, sniffling when you want to breathe in his cologne, “love him so much, Nii-san, if I lose him, I’ll… I’ll die!”

Sero sighs, “we can’t have that now, can we?” he pushes you gently away from him by the shoulders and looks at you with love, “look, I’ll help you out, okay angel? I don’t want you to die, after all,” there’s a hint of amusement in his voice but you don’t catch it as joy washes over you, “but it’ll have to be our little secret, yeah?”

You nod and wipe your eyes, “of course, of course, Nii-san! I don’t want anyone to know either, that’ll just make him break up with me so,” you sniffle as you turn your hands into fists, “I promise, I promise so please help me!” the words are stumbling out of your mouth at record speed as you sit up on your haunches to face your brother better, “Nii-san, just tell me what to do and how to do it and I’ll do whatever it takes! I’ll even use up all of my saved-up allowance!”

Your brother laughs, low and scratchy in his throat, “nah you won’t have to do that, yeah? First time’s free,” he jokes before he clears his throat when you don’t laugh and squeeze your shoulder, “look, we’re short on time, so I’ll have to be the one to teach you, yeah? But I’m home all weekend, I promise I’ll help any way I can.”

You gulp before you nod, “Nii-san will… be my first?”

Sero’s dick twitches in his shorts at your question. You’re trying your hardest to hide the shaking in your voice and it makes him want to devour you. He’s barely able to contain his excitement at this situation; what type of luck is this? Fucking Shinsou’s little sister has made him braver as he nods and crowds your space, “yeah, but I’ll be gentle, okay? And I’ll make sure you understand it all, so you don’t sound like a virgin on Tuesday.”

You grab at the hem of your shirt and move to pull it up but Sero stops you with a snort, “hey, whatcha doing?”

“Taking my clothes off. For sex.” Your voice is heavy with confusion. Your brother laughs and shakes his head, “no, no, don’t treat it like a transaction. You won’t be entering his bedroom on Tuesday and dropping your clothes immediately, right? You said you’ve been kissing him, yeah? How far did that go?”

You bite your lower lip as you think, “we haven’t even used tongue.”

Sero holds back a groan with his entire body, dick drooling precum at your confession. What the hell. He’s thrilled that he’ll be his baby sister’s first of everything.

“Let’s start with that, right? When you were kissing on the bed it felt… nice, yeah? We’ll start there, because the transitions need to come naturally.”

You lean forward in your seat and pucker your lips, eyes closed shut waiting for your brother to kiss you. Sero almost wants to snap a picture but it’s one thing having physical evidence of someone else’s little sister full of his cock, a whole other to be found having sexual interactions with your own sister. He sighs and grabs your chin with his own, tilting your head, “relax, ‘s just me, yeah?”

You whine when your brother’s lips touch your own. Through the years he’s given you numerous pecks; on bruises, your cheek, and forehead. He kissed your lips on your 10^th birthday because it was the only thing you wanted from him as a present.

But this one is different.

He sighs into it as well before he pulls away but immediately kisses you again after, the smack of his lips connecting with yours making blood rush to your stomach. Just like when your boyfriend kisses you softly and slowly like this.

You whimper when his warm tongue goes over your lower lip, like he’s silently asking for something. What are you supposed to do now? In a panic all you do is open your mouth wide to let him in. Your brother pulls back with a laugh that makes heat travel to your face and your fists clench on your lap, “oh my sweet little girl, take it easy, yeah? Follow my lead.”

You nod and breathe in deeply, “okay, ‘m ready Nii-san.”

He slots his lips back against yours, his mouth half open. You try and mimic his movements and when he chuckles lowly into the kiss it sounds so good that you moan before you can help it. You cut if off halfway but it’s still so loud in your own ears that you pull away and hide by his neck.

Your brother doesn’t laugh this time. He’s drawing circles into your back, “you’re too tense. Try and lie down, okay? Maybe it’ll help you relax.”

You don’t say anything, just follow his movements as his hands guide you down the bed, watching him silently with doe eyes as he moves a pillow to make it more comfortable for you. The sheets smell like detergent. He hasn’t slept in them yet and your mother washed and changed them before he arrived. You’re almost sad that they don’t carry his scent, so you wrap your arms around his shoulders and pull him down on top of you with a whine stuck in your throat.

He smells so nice, so safe. There’s a hint of the shaving cream your father also uses, but his cologne makes your back arch ever so slightly, body pushing back against his own. Your heart is beating so fast and it’s confusing you because this is your brother.

He’s making you experience all the same physical things that your boyfriend does when he kisses you, but it feels heightened somehow, elevated. Your brother noses at your scalp with a sigh, “we’ll take it in your tempo, right? We have all weekend.”

It’s already past dinner and a weekend isn’t actually that long. You need to hurry if you don’t want your boyfriend to hate you in a few short days. With renewed determination you pull away to face your brother again and pull him into a kiss full of conviction. You want him to teach you. You need him to teach you.

You slid your tongue against his lip slowly, and when he opens his mouth for you, something tightens in your stomach. Unsure of the next step, hovering against him like that, you taste his breath on your tongue and shiver. You squeak when you feel his tongue against yours, wet and slimy as it dances around your own, passing your lips and licking at your teeth.

You mewl as he gives you another close-mouthed kiss, shifting between innocent, sweet pecks and his tongue exploring you, keeping you constantly on edge.

You fall apart underneath him. His hands wander as his mouth takes full control of you, sedating you, making you unable to move even the smallest muscle. He pets at your arm, your hip, your waist. When he finally, finally grabs at your chest like you didn’t know you wanted, you moan around his tongue, marveling at how big his hand is around you.

“That’s it, good girl.” He whispers before he kisses you again, the smack loud and wet.

You’re dizzy with how big your big brother suddenly is above you. His long limbs are caging you. Big, engulfing hands claiming whatever he likes of you, the expanse of his chest never ending. You feel yourself drool as you try and focus on his face. Are you doing this right? Is he smiling?

Sero can’t get over how absolutely fucked you already look after a little tongue, eyes unable to focus on anything with your pupils blown wide, looking down at his thumb as they circle your nipples through your clothes. He’s not usually dumbfounded, always ready with a quick remark or praise but he feels spellbound. He’s terrified that talking will break the magic of having you here, wanting him.

Your pigtails are fanning out on his pillow and he realizes he might be just as drunk as you are right now. He laughs and you respond with a giggle that transforms into a moan when he pinches you through your oversized shirt. He realizes that it might be one of his old ones and groans.

“Nii-san, am I using my tongue right? Can we try again?”

He pretends to consider it as he hums, “’m not sure you’re doing it right angel, but I promise you’ll get it under control in no time, yeah? C’mere.”

It’s dizzying that you’re so willing underneath him, so sweet and innocent. He can’t help but be a little rough with his kissing, his tongue diving in and fucking your mouth, licking your canines and your molars. Every moan you let out underneath him is stunted, like you’re trying to hold them back and cut them off. It’s adorable.

And it’s so fucking sexy.

His hand travels down your chest and over your tummy, pudgy and soft. The elastic waistband of your home shorts won’t be hard to breach, but Sero feels his hand shaking ever so little. This is his own little sister. The youngest, the baby of the family. His baby.

“See, baby, now that we’ve kissed a little, taking off clothes is the next step, yeah?” he clears his throat, unbelieving of how hoarse he is, how shaky it feels to speak. You hum and sit up on your elbows before you pull at your shorts. He expects you to pull your panties down with them, but his dick twitches when he sees them over your cunt.

They’re white. Basic. Innocent. The ones that many young girls use and they’re thoroughly soaked.

The outline of your pussy is clear as day, distinction between your pussy lips so obvious that he bites his lip to hold back a moan. He has to remind himself that he needs to help slid the shorts off of the rest of your legs, kissing your ankle as he pulls them off of your feet. You giggle, “Nii-san those’re my feet,” you point out and he smiles down at you, eyes glinting, “yeah? Some people love feet.”

He doesn’t, but he still kisses down the expanse of your foot, looking down at you with a shit-eating grin, watching your embarrassment grow with every dramatic, wet smack before you pull your leg out of his grasp easily and kick his shoulder, “Nii-san, be serious,” you groan. It might be your most used sentence against your brother.

Sero sighs deeply as he pulls off his shirt, purposefully flexing his abs just to show off a little; he’s not a Pro Hero for nothing, right?

Before he completely removes the shirt, he peeks at you from under the fabric and watch you subconsciously lick your lips as you look at him, eyes lidded and heavy. He throws it in a random direction before he bends down back over you and kisses you quickly.

When he pulls away, you chase him with a whine, tongue already sticking out to taste more of your brother’s mouth.

Sero has always spoiled you, so he kisses you back with fervor, hands grabbing at your jaw and nape to have you as close as humanly possible.

You look up to him after with doe eyes, “what’s the next step?”

Sero chuckles and pulls at the hem of your shirt, “well, I’m still wearing pants and you’re still wearing my old shirt. You need to be patient, pace this, sex isn’t only penetration, okay?”

Even if he’ll only get to fuck you so that you can have sex with another man, Sero will make sure that he still teaches his baby sister right.

You groan and roll your eyes at his lecture before you pull off the shirt, your tits bouncing with the movements right in your big brother’s face. You move to try and get his pants but…

He can’t be blamed for wanting a taste, right?

You yelp when he pushes you back down by the collarbone and latch onto your baby tits, groaning at the feeling of your nipple hardening from the swirling of his tongue. You let out shaky whimpers above him, watching him with furrowed brows and mouth hanging open, jaw slack. Your hands pull at the strands of hairs in the back.

Your brother looks so desperate, so hungry as he licks and sucks, his other hand pinching and massaging. “Nii-chan, c’mon, need more,” you whisper. Your pussy’s been tingling, clenching and throbbing. You almost feel neglected despite the attention that he’s giving you. You pout down at him.

He pulls back with a smirk, “what part of pace yourself did you actively ignore?”

You sigh, “all of it. C’mon, Nii-chan. Please.”

You know it’s unfair to moan the last work but you’re getting agitated. If you only have this weekend and he’s going to spend the first evening just sucking and licking your breast, you won’t seem experienced by your next meeting with your boyfriend.

Even if what your brother is doing feels good.

Sero’s been spoiling you since you were born, always taking care of you when you got sick or injured, always defending you when you had spats with your parents no matter how ridiculous you’d been acting. You’re his weak spot. His favorite. But he also enjoys teasing you and keeping you on edge. Hogging the controller to the video game, stealing your snacks and spending extra time in the bathroom if he knew you were in line.

“Where do you want your Nii-san to touch you? Here?” he brushes a knuckle over your slit, watching you jump and whine in surprise at the touch.

Since you don’t say anything, he sighs and draws his hand over your navel, “or here? That’s not a very sexy spot.”

You groan at him, “Nii-san!”

Sero laughs before he goes back to your cunt, “relax angel, I won’t neglect you, yeah?”

He lets his hand drag back and forth on your slit, eyes rolling back at the sticky softness behind it, “how much have you tried?”

You gasp as you try and think, the foreign experience of another person’s hand on you, unknowing of when he’ll apply pressure or not making your head spin, “uh—hnng, m-my fingers, and,” your head falls back against the pillow as he pushes harshly against your clit, “there,” you interrupt yourself as you start to grind against him, “…and Nee-san’s old makeup brush—ah!”

Sero almost chokes at your confession.

Images of you pushing it in and out of yourself, whining and whimpering fills his vision and he groans. He plays with your tits with his other hand, “yeah? That felt good?”

You try to catch your breath. He’s barely doing anything that you haven’t done with your hands before, but it feels so different. The pads of his fingers are rougher than your own, bigger. You want more. You swallow thickly, “n-not good enough. But I was—ahhh, curious.”

“’s good, it’s good to be curious,” he says with a cough, “that’s a good girl, look at you. Reacting so well.”

He’s almost afraid of taking off your panties.

But only almost.

You hold your breath as he pulls them off, revealing your most sacred place. They’re sticky, almost clinging to your lips. When they’re off, you instinctively spread your legs for him. You want to be good for your brother; you want more of his praise.

Sero moans as you do, purposefully throwing your panties in the direction of his own travel bag. He’ll be damned if he doesn’t get anything to keep after this.

“Sh-should I shave before Tuesday?” you ask with a shaky voice when all he does is stare, but your brother rapidly shakes his head and hums, “mhm-mhm, nuh-uh.” Is all he seems to let out, unable to take his eyes away from your beautiful, glistening cunt.

It’s embarrassing. You’re hyperaware of the way his pants are still slanted on his hips, the outline of his cock very visible. You don’t know how big a dick is supposed to be, but you feel a whine in your throat when you see the thickness. His own throat bobs as he swallows thickly, reaching out and watching you jump and whine when he drags his fingers directly through your folds, spreading them, revealing your clit.

“Now your boyfriend might be a little more nervous than I am, so you’re gonna have to help him find your clit, yeah?” he rubs at it, watching you suck in a short breath, shoulders tightening, “show him how to make it feel good.”

Your thighs are twitching and you’re fighting every instinct to close your legs, stomach convulsing as you try – and fail – to relax your muscles and let your brother do his work. He coos at you with a slanted smile, “you’re doing so well, trying so hard to relax for me.”

You mewl under his praise, over the fact that he notices how hard you’re trying. Your knuckles are turning white as you grip the sheets under you, watching intently as he circles your clit, “…will it hurt when you insert it?”

Your brother’s face shoots up to look at you, “no baby, if done right it’s not supposed to hurt at all.”

It’s all the girls talk about though; how their first time hurt and how they even bled. Sero circles your hole before he gently inserts his finger, torturously slow, “how does that feel?”

You grimace, “’s a little longer than my own fingers.”

God, you’re so tight around his middle finger. You’re sucking him in like a fucking vacuum, pretty unused hole begging for more. He bites his lower lip.

“It’ll feel a little weird at first, but tell me if you’re uncomfortable, okay angel?”

You look down at where his hand disappears from view, but he doesn’t move or add any other fingers. He sighs suddenly, “princess? You’ll tell me if you’re uncomfortable? Right?”

Your jaw snaps shut and you quickly look up at him, cunt clenching at his disappointment, at the way his finger bend at the last word. You nod as you heave in a breath, “yea—” you clear your throat, “yea uhm, yes Nii-san, of course.”

He smiles down at you, “good.”

He starts fucking into you and bends his finger at just the right place, and you’ve never really had anything press at that spongy spot inside of you so you almost pull away, heaving in breaths but still feeling breathless. Sero observes you with keen eyes, watching your pussy lube him up and he can’t wait for the glisten to be on his cock instead of his meager fingers.

“’m gonna add another finger now, you gonna take it like a good girl?”

You whine and nod, loving the way that his speech is turning into a lazy drawl, humiliated by the way that he does not seem affected by this at all.

Big brothers know so much more about the world; your heart aches suddenly at the thought of him doing this to anyone but you, that anyone could have his focus, his eyes. He’s so experienced that you have to bite back a sob. You’re so happy that you’re worthy of his time. He means so much to you.

He pulls you out of your thoughts when the squelch gets loud, the fingers reaching farther than your own, stretching you so much more. You shut your eyes tightly, embarrassment making your face heat up, “Nii-san can’t you—nng, can you maybe… not make that noise?”

Your brother grins at your question, pursing his lips to avoid laughing at you, “nah baby, this is a symphony for men.”

He purposefully fucks you a little faster, a little messier just to make the squelch even louder. You groan and swat at his sides with your leg, “Nii-san!”

He tuts at you, sticking out his tongue in a grimace, acting all innocent as he catches your leg and starts massaging the muscles in your thighs, “if you act all flustered, he’ll for sure know yer just a little virgin.”

You pout, lip wobbling as your brows furrow, arms crossing over your chest, “Nii-san, I am a virgin right now though.”

He laughs and bends down to kiss your bent knee, “you got me there, but this?” he makes your cunt squelch again, “this is just how bodies work, yeah? Don’t try and hide it. Especially not from me.” He scissors his fingers and you arch your back with a sharp inhale.

 “’s that—is that three fingers?” you heave out, looking between his wrist and his face.

Sero laughs at you, “still two, just stretching them,” he scissors them slowly so that you can feel the movement, the stretch suddenly much more obvious, “you okay baby?”

You nod and spread your legs more, “it’s—aah, it’s really good, Nii-san,” you’re drooling and Sero wants to lick it up, “but… but is it supposed to be—hnng, this overwhelming?”

Your brother sucks in his underlip as he leans down, crowding you with a soft hand to your jaw, “princess,” he starts, pulling out his ring finger to give you reprieve but you reach out for his wrist aggressively, “don’t.”

He can feel the way you grit your teeth, the way your jaw is tensed under his fingertips, “Nii-san please, gimme more. I can—I’ll take it. I’ll take all of it.”

He looks at you dumbfounded for a moment, trying to cope with his own blood rushing away from his brain. Then he chuckles and licks his front teeth, “yeah? You’ll be a good girl for me?”

You nod, “mhm, yeah, yes, Nii-san, ‘wanna be your good girl.”

Fuck, your voice is so high-pitched and sweet that Sero almost can’t take it. If he didn’t know you, he’d think you’re doing this on purpose. He kisses you and feels the way you tighten around his fingers, “greedy little sister, always begging for more than she can handle.” His voice darkens as he fucks you in earnest now, thumb rubbing at your clit, “I’ll give it to you, fuck, Nii-san’ll give you everything.”

He licks at your open mouth, mewls and whimpers flying up an octave with the way he speeds up. You barely flinch or cry out in pain when he adds the third finger, wet cunt pliant and opening up for him beautifully. “Shit, good girl, good girl…” his own brain is turning dumb with the way you keep your mouth open for him, jaw aching from the stretch.

You raise an arm over your face, “Nii-san, ‘m gonna cum, I’m cumming, don’t look at me when I cum, pleaseeeee.”

Despite trying to hide yourself, Sero rips away your arm as he fucks you intently, watching bliss wash over your face and soundless moans trying to escape your lungs. There’re fat globs of tears by your lash line, but they don’t stray farther away from you as you let out the sweetest, short ah-ah-ah-ah’s when he makes you ride out the wave, hips rutting against his hand as your core shakes and throbs.

When you calm down, you open one eye to look up at him with a sniffle, “Dummy Nii-san, told you not to look.”

“Sorry, sorry,” Sero lets out half-hearted before he rubs his nose against yours, “but you looked so good, Nii-san couldn’t look away.”

Now both eyes are opening and widening, “really?” you ask, pupils blowing out, “I didn’t look stupid? Scrunching up my nose?”

Sero snorts, “the nose thing is the cutest. Nii-chan does the same,” he reassures you, kissing your cheek. You groan and blanch, “Nii-san, I don’t wanna be cute. I wanna be sexy.”

Your big brother shakes his head before he grabs your hand and leads it to his own crotch, nosing at your temple, “you can’t be both?” he whispers.

You shiver as he makes you apply pressure on himself, your eyes locked to the way he grinds against your open palm, sighing directly into your ear, “you’re making me completely lose my mind, you’re so fucking sexy.”

Your pussy throbs at the view, the roll of his hips addicting, abs flexing. You try to grab at the length through the fabric, thumb grazing the sensitive head, hoping you won’t be completely useless. Your brother shudders above you as he loses his composure just a little. You want him to lose it completely, though. You need to see it happen. Your eyes rake up his body to his face, his mouth hanging open, straight teeth on display with his eyes closed.

He swats you away with a flutter of his lashes before he starts unzipping his pants. You watch greedily as he pushes them down, thick cock jumping out and bobbing towards the bed, white fluid dripping from the head. You hear the thud of his pants and underwear hitting the floor but you don’t move or say anything until you watch him grip his own length and tug at it, “fuck, and I wasn’t allowed to stare.” he says, grunting as he drags the skin back, exposing the head completely, “you’re no better.”

You catch his eyes with your brows furrowed, “who raised me to be a brat?” you spit, hoping your voice isn’t as high pitched as it feels.

He laughs. It’s breathless and short but so sweet and addicting. Your clit aches. He kisses you quickly, “touché.”

Sero should ask about condoms, teach you about contraceptives but he almost doesn’t want to. All he wants is to fuck into his little sister’s greedy hole and leave his mark, claiming your pussy for himself. He stretches his shoulders for a moment before he stunts out awkwardly “condoms.”

Okay, that didn’t sound cool at all. But who can blame him with his dick hard and aching and a willing babypussy right underneath him? Your legs are spread and your arms defenseless as if all you’re waiting for is your big brother to force himself on you.

He laughs and shakes his head. When he’s about to open his mouth again to explain, you interrupt him, voice equally stammering and nervous. Your arms are crossed over your stomach as you look away, “mom got me on the pill years ago because my period was making me miss school.”

Ah. Must be hard being the smartest child out of all four of you. Your big brother doesn’t envy you; he’s always enjoyed being a simple kid living a simple life.

Even after all the bad things that happened at U.A, their parents have never expected more of him. He’s never done anything wrong in their eyes. A golden child, their perfect son.

Yeah, a perfect son indeed. About to be balls deep in their beloved prodigy.

You sit up and reach for his dick, “I love you Nii-san, you can do it without bu-“

“You are not letting that boy do it without though!” Sero interrupts you before he sucks in a deep breath, your small fingers reaching him and flinching when they feel the warmth, fingers shaking as you grip him like he’s some sort of scared animal. You roll your eyes at him with a groan, “if you hadn’t interrupted me, I would’ve promised you that.”

You tug at him; eyes locked onto the way precum dribbles out every time you pull forward. Sero hisses but ignores your scolding, “yeah, drag your thumb over the slit before you go back,” he instructs, heat a sharp coiling inside of him, threatening to snap at any moment.

If he could just pull your face down to his fat cock and drag you back and forth by your pigtails.

“Like this?” you whisper, and thumb at his slit, gasping when the precum dribbles directly onto your digit. Sero swallows thickly, “yeah, like that.”

He watches you for a moment before he pets at the crown of your head, “twist your wrist and grip halfway.”

You knit your brows in frustration when you don’t get what he means, “how?”

Sero puts his hand over yours and guides you up and down, introducing the twist on the third tug with a low sigh, “yeah, good girl, and then again.”

He guides your hand a few moments more before he lets go and watch you do it on your own, hand soon soaked by the precum gathering and lubing up his length. He throws his head back with a groan, “atta girl.”

You hum, “…will he like it as well?”

Sero slowly starts thrusting into your grip, back and forth, back and forth before he swallows, “yeah, bet you’ll make him cum before he’s even inside of you.”

You whine at your brother’s promise, licking your lips, corner tugging up carefully, “will you?”

Sero scoffs and puffs up his chest, “please, I got years of experience ahead of him.”

You giggle and lie back down, taking your hand coated in him and guide it to your pussy, mixing it with your own juices and dragging it through your folds. With a whine you catch your brother’s eyes, “Nii-san, want more of this on me.”

Sero blinks rapidly, controlling his breathing and trying to will his orgasm away. “Shit man,” he curses, crawling over you with his cock in hand, “who taught you to be so fuckin’ lewd?”

You lick your teeth with a grin, smugness oozing off of you, “please?”

He shakes his head, “what do I even have to teach you?”

You pout, wrapping your legs around your big brother’s waist with a sigh, “more than a makeup brush can.”

“Urgh,” your brother clenches his eyes shut to control his imagination. He wanted to have the upper hand in this situation, but apparently his little sister is just one big deviant. He grabs your jaw with his free hand, “behave, young girl. You’re way too debauched for a virgin.”

You move your head so that you can get his thumb into your mouth, licking over the digit, watching his face fall when you start sucking on it. Your big brother’s favorite pastime may be to make you the butt end of a joke, but you’ve not been raised by three unruly siblings your whole life to just let them have the high ground in every situation.

You hope he doesn’t see past the facade and notice your anxious heart racing full speed ahead.

Sero drags his thumb around your mouth while he drags his dick back and forth your slit, coating himself in your wetness, “y’know that I’ll pull out if it hurts you, right?”

You freeze before you gather the courage to look into his eyes. Your brother gives you a loving an reassuring smile before he cups your cheek, “baby, being nervous is normal.”

Your underlip juts out as you let out a shaky breath, blinking away unshed tears, “’m not nervous.” You state matter of factly. Sero laughs, “of course you are. It’s your first time.”

He leans down to kiss you, soft and sweet and innocent. You lean into it with a sigh, “be nervous. Be excited. Be scared. But tell me about it, okay? Nii-san's got you.”

His eyes are so black. So beautiful. They’re dark and swirling with love, waiting for you to give the go ahead. Even with your teasing, he still seems so unaffected, so nonchalant.

It’s only his leaking cock that’s giving his real feelings away.

You groan and look away, “Dummy Nii-san,” you mumble before you reach around his shoulders and pull him down so that he can’t see your face anymore. With your lips right next to his ear, you whisper, “Nii-san, please, fill me up.”

You’re surprised when he moans right back into your ear, surprised by the effect you have on him. You can’t fathom that your cool and strong big brother, Pro Hero Cellophane, is interested in you.

You love your Nii-san so much. You can feel yourself drip down to your ass, throbbing and clenching and dripping. You want your Nii-san to love you as much as you love him.

You feel him circle your hole with his cock, teasing the breach again and again and again. enough to make you claw at his shoulders, legs locking tighter around him, “c’mon Nii-san, I’m not a baby, I can take it.”

And then he pushes in. It’s only the mushroom shape of his head but it knocks out the air in your lungs, back arching as your body tries to figure out if it wants him to leave or come closer.

He groans, pulling out again to let both of you catch your breaths, “fuck, you’re tight. Relax princess, c’mon, relax for me.”

You kiss and lick at his collarbone, “’m trying, ‘m trying Nii-san.”

You’re not sure if you are. You’re choking on your desire as he drags himself through your folds, catches on your hole and pushes in, and then drags it over your folds again. With every penetration, you relax just a little bit. Like taking the head becomes easier and easier.

Your brother sighs as he straightens up to look down at you, “shit. Getting your cunny all dirty,” he says dryly, slanted smile on his lips as he watches his sticky precum peek out through your folds. He reaches down to pinch and circle your clit as he pushes in again, holding it longer than last time.

It’s like you’re sucking him in now, the pulsing trying to pull him further and further inside, catch him and never let him go. Your eyes are shut tight as you take half of him, secret praise whispered between you, clit throbbing painfully as your walls stretch to take your brother’s dick.

You’re afraid to look at him, afraid that he might be disappointed as he feels your insides for the first time. You fear that he’s just praising you because you’re the baby of the family, because he’s always spoiled you like nobody else. Sero’s a good liar. You know that because he’s lied for you thousands of times to your parents’ faces.

What if he’s lying to you right now?

You sob when you feel him bottom out and he freezes above you. “Hey, hey, princess, look at me.”

You shut your eyes tighter and Sero’s about to pull out when you don’t reply, but you tighten your legs again, “no, Nii-san, stay,” you cry, sniffling with your breath jumping.

He coos and hushes and kisses your cheeks, “look at me, angel, hey, c’mon,” he coaxes. After a few more kisses you manage to peek through your lashes. Your brother’s face is red as a beet, breath labored as he waits for you to tell him that you’re okay.

“There’s my babygirl,” he praises when you manage to open both of your eyes, “does it hurt?”

You turn your face to the side in embarrassment, sniffling loudly once, “nuh-uh.”

He snorts, “first dick so good it got you cryin’ then?”

It’s a joke, but Sero sees the way your face contorts for a split second and he knows your tells well enough to know how you’re feeling. He smiles proudly before he ruts into you gently. Despite doing it in slow motion you still yelp and tighten around him.

You bite your lower lip as he starts moving slowly. You’ve adjusted well to his girth and you’re so drenched that he slides easily back and forth. You’re like a lubed up fleshlight and it has him shivering, ass clenching as he tries his best to not cream you prematurely.

He promised you that he’d have all weekend to train you but he’s not sure how many moments like these that he can positively steal between his mother’s excitement of having everyone gathered for once, and his father’s pride at spending time with his Pro Hero son. Your gummy walls suck him in greedily.

You’re warm and syrupy and he peppers kisses all over your face as he pulls out. You whine from the emptiness but he hurriedly pushes back in, “gooood girl,” he drawls, watching drool trickle down your cheek.

You’re staying as quiet as you can, trying to win the detached competition that you’ve created in your mind while your brother tries to coax out your true feelings with praise and cock. You’re so childish and competitive that he almost laughs at you.

“Doing so well my angel.”

The loud echoes of your big brother’s hips slapping against you has you clenching your eyes shut again. It’s almost becoming impossible for you to hold back those unsightly moans that keeps leaking from your heart. Your brother shakes his head before he leans down to your ear.
He’ll let you have this, spoiling you again like he’s always done. Even if he took the last piece of chicken before you at dinner, he always shared it with you after you started crying.

“Fuck, you feel how hard I am?” he trusts slowly in and out, “feels so good inside of you, Nii-chan’s so close to cumming.” He moans as he thrusts in to the hilt, applying more pressure to your clit, “never felt a better cunny in my life.”

He licks at your ear as he moans, purposefully laboring his breathing more to egg you on, “you’re making your Nii-san feel so good, I won’t last as long as I usually do.”

You pussy tightens around him and you turn your head slightly, “r-really?”

Gotcha.

Sero nods and breathes into your ear, “mhm, now c’mon, lemme hear your voice. Won’t cum if you don’t moan for me.”

Ah, ah, ah, ah, ah.

Fuck, you sound so sweet now, letting him hear your high-pitched moans even if they’re embarrassing you. He fucks you harder, groaning and licking at your face like he really wants to devour you.

“Nii-san, Nii-ss—I’m cumming, ‘m gonna cum again.”

Your brother kisses you deeply, letting you taste the sound of his groans through the softness of his lips against your own. You try and match them, mewls dripping off of your tongue as he sucks on it, smiling down at you. When you throw your head back and arch your back his face still follows yours.

He breaks the kiss to moan, “fuck, you tightened up. You like that? Nii-san’s big dick filling you up?”

You lick at his mouth as he speaks, small hands grabbing at his hair, pulling at the soft locks as you try to move your hips to match him. Sero’s delirious as he keeps fucking into his sweet, perfect little sister’s cunt.

“Good—” you moan, clinging to him desperately, “feels so great, Nii-san.”

He laughs, pushing your sweaty bangs off of your face, “my beautiful little girl. Trying to milk me, aren’t you?”

His hand travels to your stomach where he pushes down, “feel me there?”

You whine, jaw slack as his thrusts becomes even more obvious, his hips going wild slamming into you. Your eyes are heavy and you feel sluggish, like you’re watching yourself from the outside taking your big brother’s cock like a good girl. “That’s ‘cos I’m meant to be there, yeah?” he grinds into you, catching his breath, “you want my cum?”

You sob and nod, “Nii-san please, please, use my pussy to feel good. I want you to feel good.”

Sero pulls back up to look down at your smaller body, the way your tits bounce with every thrust. It’s a shame that he can’t bite you or suck marks into you, claiming you like he rightfully should be able to, but he doesn’t want you to get in trouble with that shitty boyfriend of yours next week. He squeezes your hips instead, “angel where’d you want my cum, hm?”

You’re drooling as you shake your head, tears dribbling down into your hair, “anywhere, anywhere Nii-san. Jus’—just please use me.”

He clicks his tongue before he leans back down and wraps his arms around you, caging you completely underneath his big, adult body. He’s groaning and moaning into your neck, drooling and hissing at how you tighten around him. “You’re not something to use, you’re mine to love, yeah? Love you, love you, love you.”

His eyes are crossed, drunk on your pussy as you gobble him up greedily. Even though it’s your first time you take your big brother’s cock like a true slut, nails dragging down his back and marking him, pushing him further over the edge. He doesn’t even register your crying or your own cock-drunken confessions, his only concern right now is how much he needs to cum inside of you.

Even if he’d thought about cumming all over your little fat tummy, spreading it over your skin, coating you, the thought of being the first one to creampie your pretty little cunt pushes him over the edge.

His thrusts stutters as he bottoms out into you one last time, moaning with his mouth full of your hair as he cums, “take it, take it, take it,” he repeats in time with his rutting, balls emptying inside your womb.

And you do, like you’re meant to, scratching his scalp and pulling at strands of his hair, just as breathless as he is. He’s barely calmed down from his mind-blowing orgasm before you whimper directly into his ear, high-pitched and used, “thank you for the lesson, Nii-san.”

His cock spurts pathetically one last time before he collapses above you, “anytime, runt.”