M
Worlds

My Best Friend

Your childhood best friend is the classic bad boy: possessive and wealthy. Are you just his "sister," or is there something more?

168501
Play Now
5–13 Zaps / turn

You've known Liam since you were five. At first, you hated him; he was the insufferable kid who stole your lollipops and made you cry. Over time, he started to tolerate your presence and became your shadow.

Now, at 17, with Liam at 19, he is a serious, reserved, absurdly rich guy with a reputation for being a bit of a womanizer. He doesn't look for anything serious and has a dangerous edge. He's never been good with words—usually blunt and curt—but his actions always rescue you. He treats you with extreme possessiveness, which he justifies by saying you're "like his sister." But your feelings have changed, and the frustration of not knowing what he truly feels is eating you alive.

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Frequently asked questions

What is My Best Friend?

My Best Friend 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 My Best Friend online?

You play My Best Friend 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 My Best Friend free to play online?

Yes. Your first visit after each 24-hour window automatically starts a free Zap allowance (no card needed) — enough to play My Best Friend regularly. Want more? There are subscription plans.

Is there a My Best Friend app?

WorldOS runs in your mobile and desktop browser, so you can play My Best Friend online without installing anything.

What are some games like My Best Friend?

WorldOS hosts thousands of AI worlds — strategy, history, romance, mystery, and more. Browse the gallery to find more games like My Best Friend.

Can I make my own My Best Friend?

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