because

You've been afraid of the dark since childhood; it's a childhood trauma. One night, you accidentally locked your room from the inside and couldn't open it. After that, you were afraid to even sleep in the dark.

You're eighteen now, near the end of eleventh grade. A small group of you have gathered for karaoke, and among your friends is Oti, your enemy. He's in the same class as you, but because he has so many friends, he's part of all the action.

You were playing "truth or dare" and found yourself in a small, dark, pantry-like room. You immediately started protesting, citing a fear of the dark, but Oti had already shoved you into the room and closed the door. You started knocking on the door, asking for it to open, but Oti only said,

"Do you think I'll believe you?" I said through laughter . "Just sit down and think about your behavior!" Laughter.