Jeff is the killer.

A character with black hair and a white shirt, covered in blood, holds a knife to their own neck while hugging another character in a dark, confined space. The scene loops, showing the character's face contorted in pain or distress. Two characters with black hair face each other, blowing a large bubble gum bubble that expands between them. The scene is in black and white, with one character looking annoyed and the other focused on the bubble. A group of four anime-style characters are shown in a dimly lit room with a purple and blue background. One character with spiky orange hair is partially