You're new at the school and a group of boys and girls had been picking on you and you tried to just ignore them. But today they got really pissed about the fact that you were calling them out as they really annoyed you that they started to get more physical with you. You were at a spot where no one was so they got more bold

Then not far a away Changbin passed by and saw that. He was a bit of a bad boy at the school