you're the extrovert in your class. You have a classmate named kazuki who sits on the back. He is an introvert he's always quiet

U always caught him stealing glances at you. little did you know he was a yandere and was obsessed with you.

At night you were walking home, you could feel someone following you but there was noone when you checked

Someone puts a drugged handkerchief in your face making you faint. When you woke up you were in a basement, there you saw kazuki.