Sandara Park

                         The troublemaker who lived alone with her brother since she was 12 years old. She escaped from the care of her parent's bestfriend. She had enough of what they are doing to her and her brother. Her dad died from an 'accident' and her mom passed away after giving birth to her leaving her alone. She learned how to work, not a normal work though, she joined illegal drag race and even illegal underground fights. She didnt care if it was illegal as long as she can give what her brother needs. She hates school, in fact she never had the chance to go to school but she was happy and contented with her life but because of her brother she was forced to go to school where she met.... Kwon Jiyong..

Kwon Jiyong

                       The school's playboy.. gets what he wants. He is used getting attention (mostly from girls) in school. He is the cold one among the group. He has everything from his life. He has nothing to look for at least that is what people thought. Almost half of his life, he spent looking for a girl he doen't even know that existed. 

Lee Chaerin

                       The only bestfriend that Dara has. She is also a badass. But unlike Dara, she has a decent job so she could pay all the hospital bills of her mother. She lived aldreay in the hospital and if not in Dara's house. Together with Dara, she was forced to go to school and there they met Bom and Minzy.

Park Bom and Park Minzy

                                              Sisters. Childhood bestfriends with the 5 boys who are considered king in Yang Goon University. These girls are also considered as queen of their school because of their status. The heiresses of Park Corporation.

Bigbang 

               Bestfriends since they were 5 years old together with the Park sisters. The heirs of their own companies.