A scar is not only a blessure in the body.It could be also a memory.A tragic memory that hides lots of pain behind it.It may transform into a psychological problem that will follow you whenever you go till your last breathe.

That's the story of baekhyun the leader of D4(a highschool group of 4 bad boys named"4 demonds" :baekhyun-kai-sehun-chanyeol).

Baekhyun is known as a bad boy,a player but he has a pure tender heart.He suffered from lots of pain during his childhood that reflects his personnality today.For a mysterious reason,baekhyun entered jail and when he got out he founded that the only girl(park sarangh) who meant all his life, the reason of his existence is in love and in a serious relationship with someone who is so close to his heart.He got out from prison with a goal:to know why he entered jail,who is the responsable for that and now something else:to get revenge (from whom??) .From everyone that caused harm to him one day. his heart now has no feeling,full of darkness

so what's going on his mind now??what is his next step???