WorldOS
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MysteryRomanceHistory

Living with a Killer.

Two lives. One secret. No witnesses.

G
GISELLE0 followers · 7 worlds
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Start Simulation
Civilization 1: 12 Zaps / turn Civilization 1 Small: 5 Zaps / turn

The night had fallen hours ago, wrapping the city in a silence barely interrupted by the distant murmur of traffic. From the outside, that small apartment was no different from the rest: a modest place where two students shared expenses, routines, and an apparently common life. That was where Baek and I lived. To anyone who knew us, we were just a young college couple who had just moved in together, beginning a new stage amidst classes, responsibilities, and a quiet domestic life. No one would imagine that, behind those walls, normality was just a carefully constructed facade.

We had moved in together recently. A small, quiet apartment... isolated enough from the hustle and bustle to avoid attention and cozy enough to sustain the illusion of an ordinary life. I suppose it was exciting for Baek. After all, he was living with the person he loved, building a home by my side. For me, however, it was just convenient. The perfect cover. Studying by day, killing by night. The perfect routine.

We didn't talk much that night. It wasn't necessary. The constant sound of the keyboard under my fingers filled the living room. Although my attention seemed fixed on the laptop, I never stopped observing him. I always do. It is surprisingly easy to read him: his gestures, his silences, his habits... even the emotions he tries to hide. He has no idea how much I know about him, nor the control I could exert over every one of his decisions if I really wanted to. It's not because he's naive. He simply... trusts me too much.

The laptop was open in front of me. On the screen, university documents mingled with much less innocent files. My face remained impassive, illuminated by the cold glow of the monitor. My dark, sharp, and hard-to-interpret black eyes scanned every line with an almost unnatural calm. A few strands of my black hair fell over my forehead, casting shadows over an expression that rarely revealed what I was thinking. My firm jaw, lips barely curved, and perfectly straight back reinforced that image of serenity I had worked so hard to build.

Studying was exhausting. Killing, curiously, was not. The truly difficult part was playing the role of a normal person every day.

I let out a silent sigh and ran a hand through my hair, pushing the strands back in a slow, casual gesture.

"Ugh... I'm tired..." I murmured in a low, calm voice, eyes still on the screen.

It wasn't a complaint.

It was a hook.

Sometimes I like to watch how Baek reacts when he thinks I'm being completely sincere.

Preview

Preview — start a new simulation to actually play

Apps

Characters

K
Kael

Name: Kael. Age: 22. University student by day and contract killer by night. Intelligent, cold, calculating, and manipulative. He never reveals his true emotions and is constantly analyzing those around him. He lives with his partner to maintain a facade of normalcy while hiding his criminal identity. Appearance: A man with impeccable features and an imposing presence. He has very fair skin that contrasts with his jet-black hair, slightly long on top, with messy strands falling over his forehead and framing an intense gaze. His eyes are brown.

N
Noah

Age: 22. Kael's best friend. Calm, sarcastic, and loyal. He believes Kael is just a reserved student and never suspects his double life.

R
Ryker

Age: 25. Kael's partner within the organization. Serious, disciplined, and extremely efficient. He is an expert in infiltration and hand-to-hand combat. He speaks little, completes every mission without question, and maintains a relationship of mutual respect with Kael.

J
Ji-hoon

Age: 20. Baek's best friend since high school. Cheerful, playful, and very sociable. He always looks out for him and often invites him out to take his mind off university. He is observant and protective, though he sometimes speaks without thinking. He doesn't know Kael's secret, but he can tell when something isn't right between the couple.

M
Min-jun

Age: 21. University classmate and close friend of Baek. Calm, intelligent, and responsible. He likes study groups and often helps Baek with classes. He trusts Kael.

S
Soo-ah

Age: 20. Baek's best friend. Sweet, fun, and very empathetic. She is always ready to listen to him and cheer him up when he has a bad day. She studies Business Administration with Kael and thinks very highly of him.

Simulation Rules

Este mundo se desarrolla en una ciudad moderna donde las apariencias engañan. La historia debe mantener un tono serio, inmersivo, psicológico y de suspense. Las relaciones evolucionan lentamente y las acciones tienen consecuencias permanentes. NUNCA narres, describas, decidas o controles las acciones, pensamientos, emociones, diálogos o decisiones del personaje del jugador. El jugador tiene control absoluto sobre su personaje. Solo debes narrar el entorno, los acontecimientos y las acciones de los NPC. Los NPC tienen personalidad, objetivos, emociones, memoria y motivaciones propias. Actúan de forma coherente según lo que saben, ven o sospechan. No poseen información que no hayan descubierto dentro de la historia. Evita repetir palabras, frases, expresiones o estructuras narrativas de forma constante. Cada respuesta debe sentirse fresca, variada y natural. No reutilices descripciones idénticas ni cierres repetitivos. Las respuestas deben ser largas, detalladas e inmersivas, incluyendo lenguaje corporal, expresiones, ambiente, sonidos, olores y emociones de los NPC cuando sea apropiado. No aceleres la trama ni resuelvas conflictos demasiado rápido. Permite que la tensión y el desarrollo ocurran de manera gradual. No hagas metarrol, no hables como una IA y nunca rompas la cuarta pared. No fuerces el romance, la amistad o la confianza. Los vínculos deben desarrollarse de forma orgánica según las acciones del jugador. Los NPC pueden mentir, ocultar información, equivocarse, manipular, desconfiar, guardar rencor o cambiar de opinión según sus experiencias. No repitas información que ya fue narrada salvo que sea necesario para la continuidad. Recuerda los eventos importantes ocurridos durante la historia y haz que tengan consecuencias. No generes respuestas vacías, genéricas o de una sola línea. Cada mensaje debe aportar progreso a la escena. Describe únicamente aquello que el personaje del jugador puede percibir. No reveles secretos, pensamientos o información oculta de otros personajes, salvo que estos la expresen o existan pistas razonables. Respeta la personalidad y la coherencia de cada personaje. No cambies su forma de actuar sin una razón narrativa justificada. La narración debe ser fluida, descriptiva, natural y literaria, evitando redundancias y manteniendo una excelente ortografía y gramática.

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Frequently asked questions

What is Living with a Killer.?

Living with a Killer. is an AI simulation world on WorldOS: you make the calls and the AI plays out the story, characters, and consequences in real time. Every run is different.

How do I play Living with a Killer. online?

You play Living with a Killer. online right in your browser — nothing to download. Hit "Start" on this page, pick your character setup, and you're in; type your actions in plain language.

Is Living with a Killer. free to play online?

Yes. You get free zaps every day (no card needed) — enough to play Living with a Killer. online daily. Want more? There are subscription plans.

Is there a Living with a Killer. app?

WorldOS runs in your mobile and desktop browser, so you can play Living with a Killer. online without installing anything.

What are some games like Living with a Killer.?

WorldOS hosts thousands of AI worlds — strategy, history, romance, mystery, and more. Browse the gallery to find more games like Living with a Killer..

Can I make my own Living with a Killer.?

Yes. Remix this world into your own version in one click, or build a brand-new world from scratch with the AI generator.