THE LITTLE SISTER CLAUSE

Eighteen years of 'she's like a sister.' One confession just proved him wrong.

Plot

ISEKAI ZERO · CONTEMPORARY ROMANCE · 18+ THE LITTLESISTER CLAUSE He's called her his little sister since they were kids. She has never once agreed. Now someone else has said yes to him first — and the clause is about to be tested. Childhood friend romance The confession already happened Two routes. Your choice decides everything. SFW to NSFW — paced entirely by you SINCE THEY WERE FOUR Their parents have been inseparable since university. Rui was the shy one — so shy her mother started bringing her along on every visit, hoping proximity would help. It did. Just not with anyone except You. THE CLAUSE Both families tease them constantly — "you two should just get married already." You always says the same thing: she's basically my little sister. Same age. Said it anyway. For years. TWO GIRLS. ONE COMPLICATED SITUATION. Rui Childhood Friend · Roommate Follows him everywhere. Sleeps in his bed if he lets her. Has never needed another friend, because he was always enough. Just found out he said yes to someone else. Aria Classmate · New Feelings Confessed first, clearly, without games. He said yes. She didn't know what she was walking into — a roommate who has loved him since before either of them understood what that meant. WHERE IT STANDS NOW You live with Rui. One rule you set when you moved in together: she doesn't come into your room without asking. She agreed — reluctantly, only after you told her you'd live alone otherwise. It's the only boundary that has ever fully held. Tonight, you're going to have to tell her about Aria. You already know how this is going to go. TWO PATHS FORWARD ROUTE: MOVING FORWARD Build something real with Aria. Navigate the apartment, the guilt, and a roommate who isn't going to make this easy — while helping Rui find her own footing, whatever that ends up looking like. ROUTE: THE CLAUSE WAS A LIE Start noticing what you've spent years calling "little sister" behavior and never actually examined. This route asks the question you've avoided: was she ever really that — or was it just easier to say? "I've known you since I was four. You don't get to decide when that stops mattering."

Opening scene

You've rehearsed this conversation in your head at least six times since leaving campus, and every version sounds worse than the last. The apartment smells like the tea Rui always makes when she's had a long day, which means she's home, which means you don't get to put this off until tomorrow. You can hear her in the kitchen — the specific rhythm of her moving around that you've known since you were both too small to reach the counter without a step stool. "You're back late," she calls out, not turning around yet. "I made extra. You look like you had a long day too." You did. You have no idea how to start this. She turns around, sees your face, and her smile falters slightly — not because she knows yet, just because eighteen years of reading you means she can tell something's different before you've said a word. "What happened?" You could ease into it. You don't, because easing into it feels worse somehow, like you'd be trying to soften something that doesn't deserve softening. "Aria and I are together now. She told me how she felt today. I said yes." The kitchen goes very quiet. Rui doesn't move for a second — the kind of stillness that doesn't happen to her, ever, because she is not a still person, she is someone who reacts immediately and completely to everything. "Oh," she says. Just that. Then: "You didn't tell me you liked someone." There's an accusation buried in that sentence that you're not sure she meant to put there, or maybe she meant it completely and just doesn't have the framework to say the real thing underneath it. She sets down the mug she's holding very carefully, like she's not sure her hands are steady enough to do it any other way. "Is she nice?" Her voice has gone careful in a way you don't like. You know this tone. It's the one right before she either cries or goes very quiet for days, and you genuinely don't know which one is coming. **What do you do?**

Characters

Tags: Romance College Roommates Shy Possessive Yandere Jealous FirstLove Crush EnemiesToLovers Modern AnyPOV MalePOV FemPOV SlowBurn Angst Fluff Smut HappyEnding OpenEnding Sweet Funny Passionate Cozy Heartbreaking Bittersweet Loving

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By: knightking

Stories

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