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stepbro jungkook coming around to be a menace again

Don't Tell (Jungkook x Fem Reader)

Word Count: 4.41k(ish)

Pairing: Jungkook x Y/n(Fem Reader)

Rating: 18+/Mature/Explicit

Warnings: Unprotected sex, kissing (french and other), public sex, making out,mentions of /kinks for tattoos and piercing, teasing, grinding, slow dancing, taboo dynamics (step bro/sis), orgasms (yours and his), creampie, rough/intense sex, step bro/step sis forbidden stuff, dirty talk, praise, wall fucking, sucking (neck and lips), implied secret crush on you behavior, watching/creeping/spying stuff. Probably missed something but oh well.

Genre: PwP

AUs: Step Brother BTS/Step brother Jungkook

Summary: Your stepbrother is a brat. You barely get along but that doesn't mean you like when he shows up on a girl's night out to give you a hard time at a club. A little step sibling ribbing and rivalry goes further than anticipated.

Author’s Note: Purely an excuse to write kinky step bro smut. I liked the idea of step bro Jungkook being a menace/brat and got this suggestion from Anon (thank you and I hope you enjoy it). It's been a minute since I've caved and wrote something just flat out horny/smutty that reaches into Taboo realms.

Ignore the typos and all other oddities.

Enjoy if it's your kind of thing and you're a Jungkook stan. I enjoyed it.

Thank you for reading. If you like it and want to tell me, I'd love to hear it. Reblogging is not required but always appreciated.

Tag List: @kiestrokes @worldwideseal

It didn’t matter how long he’d been watching you. What mattered was that he finally spoke. 

“This is cute… Y/n and her friends, having a girl’s night.” 

You’d only just swallowed down your second shot when the haughty tone came from over your right shoulder. Turning revealed an equally gleeful smirk on familiar, lush lips. 

“Jungkook.” It was all you said–more sighing it and not hiding the way your eyes rolled. You and he had never hidden much from each other–especially not when your dad had married his mom and you’d become unwilling step siblings. 

He wasn’t getting less annoying as the years went by. What was previously an uneasy truce was rapidly crumbling to a simmering antagonism under the guise of sibling rivalry. Not that Jungkook was better than you. He was almost your polar opposite. As far as it went you weren’t sure what your father saw in him that they got on so well. 

Right now all you could see was the glint of his lip piercing and those eyes, shining as he leveled his best smug glare at you. And right now you wished you’d taken the offer for a 3rd shot. Especially with this little brat standing nearly chest to chest. 

“There’s a ton of space around here. You don’t have to stand so close.” You offered a milquetoast smile, forcing your gaze away enough to push his lithe form to the peripherals of your vision. There was PLENTY more to look at, even if it was all in the form of gyrating bodies on the dancefloor nearby. 

“Maybe.” Jungkook looked around, face going from smug to vaguely disinterested. Eventually his eyes were back on you—that much was clear in the edge of your vision. It didn’t quite make your skin crawl but a prickle was working its way up your arms. 

He just HAD to find a way to ruin a really nice night. But that was what siblings were prone to doing. 

Jungkook snorted. You knew the sound–the light raised lip. The sneaking view of teeth and one corner of his mouth crooked. No need to look. If you did it would only serve to bother YOU more. Per the usual standard, he seemed absolutely unbothered. 

“Interesting choice to hang with the girls, Y/n.” A loaded statement that you could see the trap buried deep inside. You shrugged, opting to ignore it for now. This was public and not the dinner table at home, or shoulder to shoulder with him at the kitchen sink after dinner, scrubbing up the dishes while you both sniped each other with backhanded teasing. 

“It’s ladies night.” You replied. Another sound–this one a chuckle–and Jungkook reached around you, snatching a waiting drink. You’d paid for it but he wasn’t going to make good on compensation. Still you swallowed hard watching the rhythmic rise and fall of his adams apple as almost all of the glass contents disappeared down his throat. After the glass was back exactly where it’d been on the table, Jungkook turned his focus on you again. 

“I was wondering. There’s a lot of people here.” His observation was dry and plain. Maybe in another time and space you would find Jungkook as hot as he acted like everyone found him, but right now you just wanted to dump the remains of that drink on his head and make him leave. 

But you didn’t own the club. It was a free country. The best bet might be to leave. 

“By all means..” You began,head tilting towards the front of the club and the exit doors. Jungkook’s rising brow and scoff told you he’d picked up the hint and dropped it again just as quickly.

“You’re a real peach, Y/n. What’s with the hostility? We’re not enemies.” 

“We’re not friends either. We’re—”

“Family.” He finished, earning your glare. It was so hot you’d hoped he could feel it boring right through his skull. But as usual Jungkook ignored your reaction. 

“We’re NEVER going to be family.” You shot back. “It’s bad enough that my dad remarried. I’m coping.”

“My mom makes him happy. Don’t be selfish by making it about you. Everyone else gets along.” 

“How fortunate for them.” You sniffed and pushed the empty shot glass towards the small gathering of glasses left by your friends. Friends who’d disappeared in various directions. You were due to join most of them on the dancefloor in a minute and that was some hopeful escape. 

Without missing a beat Jungkook moved on and pointed at the dancefloor. 

“Yes..” You sighed. “What about it?”

“You here to drink and watch people have fun or do you dance?” 

“You’re a real prick, Koo.” You gritted out, stepping away from the table. It wasn’t worth calling Jungkook out as he moved too, keeping you within reach. It was odd but not surprising at the same time. He was annoyingly close at home too. 

“You’re such a sweet step sister. Answer the question.” 

Your eyes rolled, head turning his way. Hopefully he saw it. Based on the even line of his lips, if he did he couldn’t care less. Jungkook had a phenomenal poker face.

“About what? …The dancing?” 

“Yes.” His lids fluttered in faint annoyance but it disappeared under the club lights painting his face with a rainbow of colors. 

“I can dance. As a matter of fact if you’ll excuse me—” You stepped away, going towards the dancefloor edge, where an opening was available. It was a palpable heat the closer every footstep took you towards the rabble.  

And as usual Jungkook was riding your ass the whole way, but it was..whatever, thanks to the helping hum of the shot flowing through your system. The club lights swirled and slowed perceptibly as the first hints of alcohol reached your brain. A gauzy sensation slid over your senses. Annoyance ebbed away by degrees. 

Instead you swayed back a little, feeling the bass flowing over you, pulsing. Riding your skin as your attention went out to those heads and the shadowy hands raised, waving and gesturing in time with the beat. 

“Get your ass out there, Y/n. Or are you afraid?” Again Jungkook’s voice came from over your shoulder as he spoke right to your earlobe.

Run your mouth some more, Jungkook. Watch me get a first tonight: kicked out for fighting in a club. Screw best behavior–I’ll blame the alcohol.

Your shoulders squared. Tossing your hair back, you slipped between the bodies without a backwards look. It didn’t matter if Jungkook followed you over the line, into the dark heat of the dancefloor. He could hang out in the corner all night or he could fuck off back home. You were going to dance for YOU, not to prove anything to him.

You’d barely stopped at a big enough space near the wall and one of the floor to ceiling speakers by the DJ booth and turned to face the way you’d come. No sign of Jungkook and if he was following he’d have a challenge: the bodies closed up the path you’d used as the dancing went on. 

You couldn’t help smiling and letting the sensation of the booming bass rattle inside your chest. Soon it had your hips moving and your body was doing what it did in your bedroom alone, stereo up and lights dimmed. Your spine undulated as your entire body got into the motion. 

Soon the shifting of your hips had your center tingling. You loved the music and the feeling of the throbbing heat closing in all around. It would probably have you sweating soon enough but that was what the pulled back hair and short, strapless club dress was all about. 

You’d chosen wisely tonight, grateful for the easy movement of your bare arms and shoulders. The flexing in your thighs unburdened by the hem at mid thigh. The dress material was flexible. Forgiving. Light and fitted. 

You felt good. You moved even better, head lolling back as you turned your body slowly, eyes closed. It was you feeling the music. Running fingers through your hair and humming, even if you could only feel it in your throat, not hearing a single note over the music flooding your ears. 

You’d find your friends later–right now this was your song and you needed to enjoy it for a while. 

What you hadn’t seen right away was what you finally caught when your eyes opened and you ended up facing the way you’d come before. This time the crowd had parted again–just enough a figure slipped through. 

You knew that shaggy head of hair and the tangle of bangs. The glint of silver in the lip. The tattoo, running from wrist up around the bicep to disappear under the sleeve of the black t-shirt. 

Jungkook.

Like a fucking lost puppy. But that wasn’t what you saw in those eyes. They weren’t shining with amusement or pity. It was something more…raw. Something visceral. A strong feeling rose in your belly as your hips stalled for a moment. 

Head cocked, he came closer as you grunted and turned your back. The LEAST he could do was leave you alone. There were plenty of women here and he was a single man–so far as you knew. And as far as his mom believed, an angel. 

The pressure of fingers tips running the back of your arm had fresh prickles climbing your skin. Your lips parted. He didn’t seem to hear the curse you spat with a half backward glance over one shoulder. 

Yes, his profile was right there. Right fucking there. AS USUAL. But the heat wasn’t cloying anymore. It was all slowly gathering somewhere low and tight. Somewhere under that dress hem. Your thigh muscles seized. Jungkook’s fingers curved over one hip and tugged, guiding your ass back into his hips.

One thing about Jungkook: he could move his body. He was athletic enough. Varsity something. Too many varsity “somethings” in high school and college– as you were privy to hear about at dinner too often. 

Breath caressed your shoulder. Lips brushed as he giggled. This close you didn’t need to shout and neither did Jungkook. So you heard him loud and clear.

“What’s this? Y/n does dance. Is this what you do in your room with the door closed?” 

“Go away.” You growled but didn’t pull back. Jungkook’s slow body rolling didn’t change pace or intensity, staying on beat. It kept you there as well. 

“Not a denial. I’m not leaving, sis.” 

“Don’t call me that.” The point of your elbow jammed into his belly only served to tighten muscle that was already visible the times you’d caught him running around outside with his shirt off. Or around the house–more often these days. No amount of teasing made him self conscious enough to add a layer. 

“Hmmm.. I’m sorry.” He hummed, cloying breath going right up your nape. He followed it to pause behind your ear.

“What do you want me to call you?” 

“Y/n. That’s my name. You didn’t forget that.” 

“No. There’s a lot about you I can’t forget.” 

“Creep..” You breathed as warmth feathered your lobe, then lips touched. Pecked. When teeth trapped and tugged you winced and shuddered. When your hand shot up towards his head, Jungkook’s quick reflexes caught your wrist and he guided it behind to rest at the small of your back. A few long fingers circled around the bone guaranteed you’d be hard pressed to try again. 

“I’m faster. What were you going to do, pull my hair? Not very nice of you..” 

Your chest tightened but the pounding was getting louder. Jungkook’s other palm slid up from your hip to just under your navel and pressed there. Both of you had stopped moving except for the barest sway left and right. You’d long since lost the beat. The music was a distant sound. A cover, like the sweeping club lights well overhead, none of it reaching further than your shoulders. 

Any onlooker would only see Jungkook whispering. Not exactly a sight out of the ordinary for a club at this hour. If they didn’t know the relationship between you, they’d just assume it was two people feeling the music and falling into a mood together, soon to escape and do the thing most club night hookups ended in. 

Which was the last thing that should happen with you and Jungkook. 

You licked your lips and tried to speak. “Koo—”

“Hmmm.”

It was more affirmation fueling the option your lizard brain had turned him into. An objection was desperately trying to escape to bring sense to you both.

Fingertips curled against your skin. Although your skin was warm under the dress material his touch was even warmer as he added pressure.

“What are you doing?” You finally gasped, choking on any further words as his palm descended. His touch crept lower, wandering between your thighs and they shivered then clamped tight. Your head snapped to one side, tilted sharp. “..N…No..” 

“So why aren’t you fighting me? Why do you feel so…hot? Isn’t THIS what happens in a club?” 

Breath huffed in tempo as Jungkook chuckled louder. His teeth gripped a bit of skin near your jugular and let it slip free, then he sucked the spot until a wet ring remained. 

He wasn’t far off. You’d done this plenty of times with handsome strangers whose acquaintance was hours old…or sometimes less. That was completely different—who Jungkook was created a huge problem being anything BUT a stranger. 

Cognitive dissonance built in the form of pressure behind your eyes and at the back of your head. But it wasn’t enough to make you pull away. And Jungkook pulled you even closer. The thick heat curved along your ass was familiar. And all your insides knew were that they needed to be stuffed deep. 

The name that came with it was a piddling detail. It wasn’t illegal. Morality and ethics aside. 

“We’re siblings.” 

“Anyone here know that?”

“Are you…serious?” You whined but your body just wasn’t cooperating. The fact was: Jungkook was just as sexy and good looking as every other man here, past or present. 

And right now his arm looped your waist as he backed you both through the crowd, taking the brunt of collision as he bullied you both whatever direction only he knew. Eventually the backward traveling came to a stop and the club swirled into a blur of color and light until you found a wall against your back. 

Then found Jungkook’s eyes gazing from below as he took one knee. His fingers touched your knees and climbed, taking the dress hem with it until he’d bunched it at your hips. His head bowed as he kissed the inside of one thigh, then turned his profile and nuzzled the other side. 

You swallowed down a moan and your fingers dashed through his hair, snarling and grasping. Whether it was to pull him away or closer, that wasn’t clear. Right now you were just holding on for the ride. He exhaled over the center of your panties with a groan, then buried his nose and mouth there, inhaling. His shoulders shifted as the vibration of his moan moved through your sex. 

“Koo…we’re—” 

“Shhh.” A pinching bite cut your objection off neatly. The seam of your panties shifted as he tucked most of it to one side and traced the back of a nail along your folds. It might have been the height of scandal since Jungkook knew you–until now in unassuming and mundane ways–but it was hard to think straight and do the reasonable thing. 

Instead your body followed Jungkook’s movement, pulled towards him with the magnetic energy that kept you from separating yourself and walking away. You SHOULD find your friends. You SHOULD be with them, shaking your ass and singing as you all sweated and lived your best night. 

Instead you were here as Jungkook stood again and cupped the back of your neck. He paused, lips a hair’s breadth from your own. His eyes seemed so deep and full of fire–like he saw nothing wrong with this. Like you were the hottest girl here and he wanted to devour you. 

“What are we doing, Y/n? We’re just two people.. Don’t you like it?”

“Yes..” You whined, chasing his tongue when it snuck out and followed your lower lip. His nails sunk into your nape and he tugged your mouth close, fitting his lips perfectly. The kiss was shy for a moment then you melted against the wall and Jungkook sank into you. 

He was exactly as hard as you’d felt on your ass minutes ago, but this time he slowly rocked himself against your exposed mound. And it worked: your left foot left the floor and that knee bent. He caught the back of that knee and wrapped it over his hip. 

The front of his jeans were open so fast you didn’t know when he had the time or focus while he kissed you in a way that had the world blown away–like it was you and him. In a hallway somewhere–the hallway in your house, by the front door, in the dark. Trying to keep quiet so no one in the house would wake up, come down with questions and leave with shock. 

Jungkook had you feeling totally bereft of clothes and it was a brand new experience, this raw intensity. A free hand dug deep down the front of his pants. Your grip tightened on his forearm, distracted to find the thick lines of muscle there. His heat and scent curled under your nose as he broke another kiss and gulped down a mouthful of club air. 

“Then don’t ask me to stop. I want to feel it…Tired of just seeing you. I want to know what you’re like inside. Lie and tell me you aren’t curious too. Can’t ignore it…been trying to. It’s..wrong but I don’t care.” 

You listened to the words and melted like butter around the blunt shape gliding through your folds to open them. The air was pushed out of you just a little when Jungkook’s broad chest crushed yours. He pinned you hard into the wall. Something trickled out of you and he sucked your lower lip. 

Don’t think about how wrong this is. How he’s bringing this onto us both.

But he was also right: you couldn’t deny Jungkook was an attractive guy. And he was all over you, the way you’d ached for many, MANY nights out with your girls. The way you’d hoped with every extended stare between you and strangers that hadn’t panned out. 

Your eyes screwed shut so tight that sparkles showered behind your eyes. Your lungs ached, slacked lips pulling far too much air in. Waiting, anticipation burning in your cheeks. 

“J..just ..please..” You wheezed. 

Jungkook’s cock was thick as it sank into you. Your head reeled as the world canted dramatically. Closed eyes rolling, you choked on another gasp. Pressure filled you as his cock slid inside. The stretch was so good against your reflexive tightening, earning a deep groan from his lips. His face stayed buried deep against your throat and he pulled back slowly, then went in again. Over and over, a few times until the glide was ultra smooth–wet and seamless. 

Then the pacing thrusts began. Jungkook drove into just off the beat of the music. This song was a little faster and your body bounced along, back sliding up and down the wall. The material of your dress slowly rode up with it and sweat built with the heat of your skin touching the rapidly heating club wall. 

“You’re so tight..godddd..” He marveled, sounding far off and delirious but kept on, pumping without pause. Your heel climbed up the back of Jungkook’s thigh and your calf tightened over the round of his ass. 

His lips touched your chin and his hips rammed harder. The fireworks show filling the black of your closed eyes changed colors as pleasure began to build in your stomach, then lower. The pressure was so good. And the impact was adding a bite of stimulation right to your clit. 

You hadn’t asked much about Jungkook’s private life. You hadn’t seen him coming home with anyone or around town with a girl. He never seemed to talk about it. But maybe that was why he was so hungry now, pushing into you like he’d been suffering a long sex drought. 

Your head went airy and your chest burned as you drew in another deep breath. Nails sinking into Jungkook’s shoulder through the shirt didn’t seem to make a dent in his focus. He went on and on, unabated until you almost fainted in the rush of an orgasm. The aperture of your vision shrank, leaving a pin point of strobe right over Jungkook’s head that provided just one solitary focal point. The high blew through you. Walls and thighs clenched Jungkook’s girth. 

Let god strike you and down and the devil laughingly take your soul, this felt so good your soul might depart your body as skin sang.  

As you milked his cock, Jungkook’s lips bruised yours with a shaking kiss. It was as if he was trying to climb up the wall or push you through it–either one you didn’t care, off in your own world far beyond the roof of the club or the stars in the sky. A moan of climax left his lips as  Jungkook’s tongue brushed across your lips. He gave a full body jerk, pulsing deep inside. It didn’t take a genius to figure out what was happening. You’d paid enough attention in sex ed to know exactly how dumb you were both being, among other things in this moment. 

Jungkook’s orgasm ended just as yours faded into a few lingering twitches. Carefully he released your knee and you planted that foot on the ground. He eased back and gave you enough space, watching as you panted, brushing hands over your thighs and wanting to shrivel at the slickness running down the insides. Instead of doing anything to diminish it, you tugged the dress back down and said a prayer. 

While you swept fingers along your hair and smooth the frazzled strands down with gathered beads of sweat, he redid his jeans, zipped, buttoned, then flashed a fucked out grin. The whites of his teeth were almost electric under the black lights overhead. 

That meant anything of a certain color would show too–like giant arrows pointing right to your whorish behavior. You started to sweat again for more serious and socially disastrous reasons but Jungkook’s brows furrowed when he noticed. 

Again he came close. “What is it? No one saw.” 

You scoffed, head still spinning furiously. You took his forearm when offered and he backed through the space you had, making a way for you two to head towards a dancefloor exit. Not the same direction you’d come, at least. Every step you could feel a little more fluid tickling as it dribbled inches more down your skin. 

“You’re asking me that… Were you not just there?” He was being dense on purpose, maybe. Or he was as spun out as you probably looked. Jungkook stopped at the opening leading to a dark hall as you spied the glowing sign with male and female symbols just overhead. 

Well at least he was doing a smart thing: the bathroom. Privacy enough and the means to clean up–as much as it mattered. But that also left other problems: your friends. 

“Jungkook…” As he walked you held his wrist. He didn’t look back, paused at the Women’s bathroom door. One palm pressed the dark wood and he glanced over. 

“Hmm?” 

“...What about them?” He had to know. Jungkook was no dummy–he had common sense, even if he’d parted from it tonight for a bit. Wearing fresh anxiety all over every feature, here in the yolky hallway light without the blessing of shadows and denial, there was no mistaking the rising panic in your eyes. How the fuck would you being to explain or lie to a group of people all agreed that you were the worst liar among them all? 

Jungkook’s brow rose, then he glanced back to the end of the hall, out where the rest of the club was still alive and steaming through another song. Voices, laughter and reality was back there. You weren’t ready for any of it, legs still watery and head still foggy from the endorphins swilling through your blood.

He offered a thin smile,pushed the door faintly and nodded into the gap. 

“What about them?” You growled and he relaxed with a bigger smile, pushing the door open a bit more. “...They don’t know I’m here. I’ll leave first..if that’s okay?” 

“Jesus..” You sighed. “...It’ll have to do. We…we can’t talk about this. Like…EVER. Not to them OR anyone else.” Anyone including your parents. This was such a pinnacle and low moment of the most scandalous situation you’d ever been in. 

“What should I tell your dad if he asks?” You didn’t know why Jungkook was asking this. Your dad was never one to be in your business, especially if it was a girl’s night. You were legal age by a couple years and independent. You might still live at home but you paid rent and held down a job. Your dad seemed good with assuming you could handle yourself. That status quo would do just fine for you too. 

“He won’t…” 

“But–” 

“He WON’T.” You reiterated with eyes narrowed. That earned a playful smirk from Jungkook, the piercing on his lip suddenly shining so clearly it was almost the only thing you could focus on. You HAD to get it together and go home, not making it obvious that anything had happened between you and your step brother.

Even if you liked it. God help you… the urge for more was also buried deep down. But you ignored it in favor of disappearing through the open door. Jungkook’s hand slid down as he let the door close almost entirely. You heard his words before the world was closed away. 

“You’re kind of a bad girl, Y/n. You keep it up and I might have to blow your cover.”