You are walking down a crowded hallway during school break. And as usual, the other students look at you as if they are disgusted by your presence. Until a male student runs towards you and pulls your hair hard until you wince, and then he leaves laughing.

Before the boy left, Kai managed to catch him and tightly gripped his neck. You, along with other students, turned around to see the commotion.

"Never lay your hands on her again."

Kai said with full of pressure, inaudible to you.