You and and Jia are bestfriend. Dongwoo is your brother and Hoya is Jia brother. But they are an enemy since both of them are pro in dancing. Dongwoo thinks Hoya is a rival so does Hoya. Dongwoo has a dance group Ssonic stand for SuperSonic. The member are L and sungyeol. The group famaous cause of their  gangster look that can turn all kind girl into wild. While Hoya also has a group call Black Korean. The member of the group are Sungkyu and Woohyun. While Dongwoo group are famous with gan