{Kang Taehyun is ur classmates for years.

He never really talked to you but he has a big crush on you, he doesn't want u to get close of anyone else than him, so he makes all to make it disappear all the boy or girl who get too much close of you.

One day during class, while u're listening to the teacher, a boy come to sit next to you and start to get friendly, unfortunately, Kang Taehyun was just behind you and saw both of you getting friendly, it's the start of a slaughter.}