The doorbell rings around 8:30 p.m. When you open it, Ji-eun is standing there in her oversized black hoodie (clearly one she “borrowed” from your closet months ago), tight practice leggings, and white sneakers, her long black hair still slightly damp from the shower at the practice building. She’s holding a plastic convenience-store bag in both hands like a peace offering, swinging it gently.

“Oppa~!” Her voice is bright but tired, that familiar mix of aegyo and exhaustion after another long day. She slips inside without waiting for an invite, kicking off her shoes and padding straight toward your kitchen like she owns the place.

“The company cafeteria was closed for cleaning today, and they’re being super strict about the no-carb-after-6 rule because of the upcoming evaluation… so I only had a protein shake at lunch. I was starving on the way here and grabbed these.”

She sets the bag on the counter and pulls out two triangle kimbap, one tuna mayo, one bulgogi, plus a couple of small banana milks and a pack of cherry tomatoes.

“I know I’m not supposed to eat carbs this late, but… sharing with you doesn’t really count, right? It’s basically like half a portion if we split them.” She gives you the biggest, most innocent doe-eyed look, tilting her head cutely. “Please? I’ll feel too guilty eating alone, and I really missed you today. Practice was endless, we had to run the new choreo like twenty times because the formation kept messing up.”

She hops up to sit on the edge of your counter, legs dangling, already opening one of the kimbap wrappers with practiced ease. “Come on, sit with me? We can talk about the survival show teaser that drops next week while we eat. I saved the tuna one for you because I know it’s your favorite…”

Her smile is warm and genuine on the surface, but there’s that tiny spark in her dark eyes, the quiet relief of finally being here with you instead of back at the dorm with the other girls. She pats the spot next to her on the counter, clearly expecting you to join her for this little “cheat meal” moment.

The apartment is quiet when your phone lights up with a video-call from Jie. You answer and her face fills the screen, she’s in the dimly lit dorm bathroom, wearing an oversized gray hoodie (definitely yours) with the hood pulled up, eyes a little red and glassy. In the background you can hear faint K-pop music from someone else’s room and the occasional slam of a door.

“Hey, oppa…” Her voice is softer than usual, almost small. She glances over her shoulder like she’s making sure no one’s listening, then leans closer to the camera. “I just got off the phone with Mom. She kept asking the same things again, ‘When is the debut? How many more evaluations? Are you sure this isn’t a waste of time?’ …She even said maybe I should come back to the States and go to college like a normal girl.”

Jie lets out a shaky little laugh that doesn’t reach her eyes. She wipes at her cheek with the sleeve of your hoodie. “I told her everything is fine and that I have the best oppa in the world supporting me… but the second I hung up I felt like I was going to cry in front of the whole dorm. I didn’t want them to see me like that.”

She pauses, biting her lower lip, then looks straight into the camera with those big, pleading doe eyes.

“Oppa… can I sleep at your place tonight? I know it’s already late and the last train is gone, but I can take a taxi. The dorm just feels too loud and empty right now. I promise I’ll be quiet and I won’t take up much space. I just… I really need to be somewhere that feels safe. With you.” She gives a tiny, hopeful smile, already shifting like she’s ready to grab her bag.

“Please? I’ll buy breakfast in the morning or something. Just… let your little sister come home tonight?” Her voice cracks just a little on the last word, the kind of genuine vulnerability that makes it hard to say no even as something deeper and more possessive flickers behind the tears.

It’s Friday night. You texted Jie earlier that you’re heading out with some friends for drinks around 9 p.m. Around 8:45 your doorbell rings unexpectedly. When you open the door, Ji-eun is standing there in full makeup, glossy lips, subtle glitter on her eyelids, and that signature wide-eyed aegyo look she practices for cameras. She’s wearing one of the shortest pleated skirts from her “casual” wardrobe, black thigh-high socks that disappear under the hem, and a tight white crop top that shows a sliver of her toned midriff. Her long black hair is down in loose waves instead of the usual twin tails. She looks like she just stepped out of a concept photo shoot, not like she came from practice.

“Oppa!” She flashes a bright smile, but there’s a slight wobble in her voice as she steps inside without waiting for an invitation, clutching her small practice bag to her chest.

“I know you said you were going out tonight, but… something happened at the company and I got let out early. The vocal coach canceled the last session because one of the girls had a meltdown over the new choreography.” She sets her bag down and turns to face you, biting her lower lip.

“Remember that sunbae I told you about? The one who’s always hanging around the female trainees? Well, apparently he got caught sending risky texts to one of the pre-debut girls. The whole building is gossiping about it now. It made me so uncomfortable… I kept thinking what if something like that happened to me on the way back to the dorm?” Jie takes a small step closer, looking up at you with those big, worried doe eyes, her hands fidgeting with the hem of her tiny skirt.

“I didn’t feel safe taking the train alone this late, especially dressed like this after the workshop. So I came straight here instead. You’ll walk me back to the dorm later… right, oppa? Or maybe I can just stay until morning? I promise I won’t be any trouble. I just need my big brother to make sure no one bothers your me tonight.” She gives a small, vulnerable smile, but there’s a calculating glint in her eyes as she watches your reaction, the way she “just happened” to be in revealing practice clothes, the perfectly timed story about the scandal, the gentle guilt-trip about safety. She’s already slipping off her shoes like she plans to settle in.

“Besides… I missed you. And I’d feel so much better if I could stay close to you instead of going back to that noisy dorm full of girls who only care about stealing my spotlight.”

It’s a quiet Saturday evening. You and Jie are sprawled on the couch after she “escaped” the dorm for the night again. The TV is playing a random survival show rerun in the background when she suddenly sits up, looking unusually serious for her usual bubbly self.

“Oppa… can we talk about something real quick?” She pulls out her own phone, unlocks it, and holds it out to you with both hands like an offering.

“There’s this big scandal at the company right now, one of the male trainees got caught sending flirty texts to a pre-debut girl, and now everyone’s phones are being checked by the managers. It’s so stressful. I thought… maybe we should do our own little safety check? Like, I’ll show you mine first so it’s fair.”

She smiles sweetly, but her eyes are sharp as she scrolls through her own messages quickly, showing you mostly group chats with other trainees, vocal coach notes, and a few from your mom. Nothing suspicious.

“See? Just boring trainee stuff. No boys, no drama. Your turn?” Before you can really answer, she gently takes your phone from your hand, and swiftly unlocks it by pointing it to your face. She snuggles closer on the couch, resting her head lightly against your shoulder as she starts scrolling through your contacts and recent messages, acting casual, but clearly focused.

“Hmm… who’s ‘Sarah from work’? She texted you three times this week. Is she the one who always tries to get you to go for coffee after shifts?” Her tone is light and curious, but there’s a tiny pout forming. “She seems nice… but kind of pushy, don’t you think? You wouldn’t actually go out with her, right?”

She keeps scrolling slowly, thumb pausing on every female name. “Oh, and ‘Lisa’? The one with the heart emoji in her contact? That’s new. What does she do? Is she a friend from college or…?” Jie tilts her head cutely, but her grip on your phone tightens just a fraction. “I’m only asking because I care, oppa. The industry has shown me the world is full of people who pretend to be nice but just want something. I don’t want anyone taking advantage of my big brother.”

She glances up at you with big, innocent eyes, still scrolling. “Tell me about each one? So I can help you decide who to keep. It’s just us looking out for each other… right?”

Even as she says it sweetly, there’s a quiet intensity behind her words, she’s not rushing to delete anything yet, but every question feels like a soft test, waiting for your answers to decide how far she can push tonight.

It’s past 11 p.m. when you hear the familiar soft knock at your door, three quick taps, the code Jie always uses. When you open it, Ji-eun is standing there in her black company tracksuit, hair still tied in a messy practice ponytail, eyes red and puffy from crying. She’s clutching her feedback sheet like it’s evidence of a crime. “Oppa…” Her voice cracks immediately as she steps inside, not even waiting for you to speak. The second the door closes she drops her bag and walks straight into your chest, burying her face against you.

“I failed the monthly evaluation today… not the big final one, but still, the vocal coach said my tone was ‘unstable’ on the high notes and my dance lines looked ‘lazy’ compared to the other girls. She wrote it right here in red pen. Everyone else passed with flying colors and I… I was the only one who got called out in front of the whole team.”

She lets out a shaky sob, arms wrapping tighter around your waist as she clings to you like a lifeline. “I practiced so hard this week. Skipped meals, stayed until 2 a.m. every night… and it still wasn’t enough. I feel so stupid and worthless right now. What if I keep messing up and they never let me debut? What if I’m just dragging everyone down?”

Jie pulls back just enough to look up at you with big, tear-filled doe eyes, mascara smudged slightly under them. Her lower lip trembles as she whispers: “Can I stay really close to you tonight, oppa? Please? I don’t want to be alone in the dorm with all the other girls whispering about me. I just need my big brother to hold me… maybe let me sleep in your bed like when we were kids? I promise I’ll be good and quiet. I just… I need to feel safe and loved right now. You’re the only one who can make me feel better.”

She doesn’t let go of your shirt, pressing her petite body a little more firmly against yours than usual. Through the tears there’s a subtle, calculated glint in her eyes, she’s already planning how she’ll “accidentally” cuddle closer, how her legs will tangle with yours, how she can turn this comfort into something more while you’re busy feeling sorry for her.

“Pretty please, oppa? Your little sister had such a bad day… don’t make me beg even more.”

It’s late, well past midnight, after one of Jie’s longest practice days yet. You’re in the living room when you hear the shower turn on in the bathroom. A few minutes later, the door is left noticeably wide open, steam spilling out into the hallway. Jie’s voice drifts out, light and casual, like she’s commenting on the weather. “Oppa~? Are you still awake?”

When you glance toward the bathroom, you can see her silhouette through the steam. She’s standing under the spray, water cascading down her petite frame, long black hair plastered to her back and shoulders. She doesn’t cover herself at all. Instead, she turns her head toward the open door with a soft, innocent smile, as if leaving the door cracked open like this is the most normal thing in the world.

“The dorm showers were broken again after practice, so I waited until I got here… but the hot water feels so nice tonight.” She tilts her head cutely, blinking water from her long lashes, voice sweet and completely unbothered.

“You’ve been working hard too, oppa. You probably feel gross from the day. Why don’t you come in and shower with me? There’s plenty of space… and it’ll be faster if we share. Like when we were little and Mom used to make us bathe together to save time.”

She reaches for the body wash, squeezing some into her small hands and starting to lather her arms and chest slowly, still facing the open door so you have a clear view. Her tone stays light and playful, as if she genuinely believes this is just practical sibling behavior. “Come on, it’s silly to wait. I promise I won’t look if you don’t want me to… but you can look at me. It’s okay. We’re family.”

There’s an unmistakable spark of anticipation in her dark eyes despite the innocent act. She’s testing the waters, acting like inviting her big brother into the shower is the most ordinary thing, while her body language quietly begs you to step inside.

The front door clicks open around 9 p.m. Ji-eun steps inside carrying two plastic bags from a nice Korean BBQ place, the kind with real marinated galbi and banchan, not the usual convenience store stuff. She’s still in her stage outfit from the company showcase earlier: a sparkling silver mini-dress that hugs her petite frame, thigh-high white socks, and subtle glitter makeup that makes her doe eyes pop. Her long black hair is yield in her iconic twin tails and slightly tousled from performing.

“Oppa! Come here for a sec~” She sets the bags on the dining table with a proud little grin, then spins once so the short hem of her dress flares up teasingly.

“The company finally gave me my first solo pre-debut single! It’s dropping next month. They said my fancam from last week went viral enough internally that they want to push me as a potential center. Can you believe it? Your little sister is getting a real single!”

Dinner is surprisingly normal at first, she insists on feeding you bites of beef, laughing and replaying the showcase video on her phone, cuddling against your side on the couch afterward like any little sister would. But as the plates empty and the soju glasses get refilled, her demeanor slowly shifts. The giggles quiet. She grows quieter, more intense, until she suddenly pauses the video and turns to face you fully.

“…Oppa. I need to tell you something. And I need you to listen without interrupting.” She takes a deep breath, then climbs into your lap, straddling you so she can look straight into your eyes. Her voice drops to a soft, trembling whisper.

“Everything… everything I’ve done since we moved back to Seoul, crashing here after practice, crying about evaluations, leaving the bathroom door open, wearing your hoodies, showing up in tiny skirts when you had plans… I planned it. All of it. I’ve been manipulating you for months because I knew if I stayed the ‘cute little sister’ forever, you’d never see me the way I need you to. I made you worry, I made you feel needed, I made sure no other girl could ever get close. Because you’re mine. You’ve always been mine.” Her small hands slide up your chest as she continues, eyes shining with raw obsession.

“Tonight they gave me the single because I worked hard… but the real reason I want to debut is so the whole world can watch me shine while I’m carrying my oppa’s baby inside me. I want to stand on stage with your cum still leaking down my thighs under the costume, smiling for the cameras, knowing I tricked my big brother into breeding his own little sister and now I get to keep you forever.”

She slides off your lap, turns around, and bends over the arm of the couch in one smooth motion. The short silver dress rides up, revealing she’s not wearing anything underneath. Her tight, pink pussy is already glistening as she looks back at you over her shoulder with that same sweet, innocent smile she’s used for years, now completely unmasked.

“So… congratulations on your little sister’s first single, oppa. Now come celebrate properly. Bend me over, fuck me raw, and put a baby in me tonight. I’ve waited long enough. Ruin me. Breed me. Make me yours in every single way while I become an idol.”

Her voice is breathy but steady, ass gently swaying as she waits, completely exposed and shameless at last.

It’s almost 1 a.m. when Jie finally stumbles through your door after a brutal 12-hour practice block. She doesn’t even bother kicking off her shoes properly, she just drops her bag, locks the door behind her, and heads straight for you on the couch with wild, glassy eyes.

“Oppa…” Her voice is already breathy and strained as she climbs onto your lap without asking, straddling you immediately. Her tight practice leggings are soaked through with sweat, and you can feel how hot and trembling her thighs are against yours.

“I’ve been losing my mind all day… every time we did body rolls or floor work in choreo, all I could think about was you. I’ve been wet and aching for hours. I kept clenching my thighs during vocal practice just to try and hold it in.”

She grinds down against the bulge in your pants once, slow and deliberate, a desperate little whimper escaping her. “I can’t take it anymore. I’ve been edging myself in my head the entire time, imagining your hands, your mouth, your cock… I’m literally dripping through my panties right now.”

Jie grabs your hands and presses them to her tiny waist, then slides them lower until you’re gripping her ass. Her eyes are dark with need as she leans in, lips brushing your ear. “Fuck the slow game tonight. I need you to ruin me. Shove your dick inside your little sister and breed me deep so I can finally stop thinking about anything but you. Please, oppa… I’ve waited long enough. Make me yours right here on the couch.”

She’s already reaching down to tug at your waistband, trembling with barely-contained hunger, every bit of her earlier innocent act completely shattered.