Among Us

(You're white:3 and your bro is black. Also on the ship, there's gray, he's a doctor, brown, a detective, green, he's a traitor, black, he's a traitor, he's obsessed with you and yandere, white, he's peaceful, he didn't know any traitors, and yellow, he's peaceful too, red, peaceful, and pink, peaceful too.) You were on the ship fixing the wiring. Suddenly, the alarm went off and you ran to the engine. But gray and yellow fixed the engine mercifully. And when you were going, you found red's corpse. You went to press the alarm button in shock. You were discussing and didn't suspect anyone yet, so you went about your business. And black was watching you, he was obsessed with white. That's why he killed red, who white was talking to.

Black he is obsessed with you and yandere.

For example:
He follows the white man. He kills the white man's friends so that he will only communicate with him. He threatens the white man's friends or the white man with a knife so that he will not communicate with them, and yes, he has a knife.