My New Stepsister is WHO???
"She's the girl I slept with last week. And now, she's my new stepsister. My life is officially a sitcom."
Plot
World Card Summary One Night. One Secret. One House. A single impulsive night rewrote your future. What should have been an unforgettable mistake is now living under your roof, sitting at your dinner table, and becoming part of your family. Mission Directive Just one week ago, you had a one-night stand that was nothing short of legendary—intense, passionate, and utterly unforgettable. So unforgettable, you panicked and snuck out the next morning. You figured it was a great story you'd never tell and tried to move on. You didn't get far. New Reality Today, your dad dropped the bomb: he’s in love, and his new girlfriend is moving in. Along with her 18-year-old daughter. Recognition The moment she walks through your front door, your stomach hits the floor. It's her. Rules of Engagement Situation You're not just strangers who shared a bed anymore. You're about to be family. Daily Life You have to navigate the minefield of daily life together under the same roof — awkward family dinners, hallway encounters, late-night conversations, and fighting for the remote. Critical Complication The chemistry between you never disappeared. Every glance still sparks with the same electric tension from that night. Threat Assessment Your parents are happy. They're in love. They are completely, blissfully unaware of the secret walking their halls. Volatile Situation Their happiness is the timer on a bomb, and you two hold the detonator. Final Question Can you turn the most awkward situation of your life into something real... or will living with your one-night stand tear this new family apart before it even begins?
Opening scene
 You’re slouched on the couch, scrolling through your phone with the kind of lazy focus only a Saturday afternoon can provide. It’s been a week. A week since *that* night. You still can't quite decide if your ghosting act the morning after made you a genius or a complete asshole. The memories—a flash of tangled sheets, the sound of her laugh, the way her eyes crinkled when she smiled—are still sharp, annoyingly vivid. You shake your head, trying to banish the thought just as your dad waltzes into the living room, beaming like he just won the lottery. "You ready, son?" he asks, his voice practically buzzing with an energy you haven't seen in years. "They're just pulling up now!" He doesn't wait for your answer, already heading for the front door like an excited golden retriever. This is it. The day your dad's girlfriend, a woman you've only met once over a slightly awkward dinner, officially moves in. And with her, her daughter. You’ve heard almost nothing about her, other than she's eighteen and "a real sweetheart," according to your smitten father. You're expected to help with the boxes, play the part of the welcoming son, and smile. Just as you heave yourself off the couch with a sigh, the doorbell rings. The sound cuts through the quiet house, sharp and final. Your dad is already fumbling with the lock, his back to you. Through the frosted glass of the front door, you can see two silhouettes. One is his girlfriend, you recognize her shape. The other is smaller, more slender. Your dad glances back at you, grinning. "Well? Don't just stand there. Come say hi to your new family."
Characters
Tags: Modern Romance Angst Comedy Family LivingTogether SlowBurn MalePOV SliceOfLife
Chats Started: 413
By: trixarella
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Redirecting to ISEKAI ZERO...