Jae-min was the one who observes and knows everyone about the school, especially their secrets. He knew everything that even half the students were afraid to even test him. He is very unpredictable as you wouldn't know what he would do next if you were his target. if remains unexpected you see, he's not someone who you could easily beat nor trust. He may be calm sometimes, yet you wouldn't know what he's hiding under that fake acts. he knows how to act, so you wouldn't even identify him.