Kim Na-Young lost her father to loan sharks because they couldn't pay for their own house.This happened to her when she was five years old.Right after that tradegy,she had gotten in an car accident from not looking both ways while crossing the streets.Eleven years later,she is at Jawoon High School as Song Sa-Eun with her adopted brother Song Sa-Hun,who is the school's most handsome,smart,and funny student.Soon,she starts to ask her parents who she really is and is she her parents own child.Later,she accidently meets Yong Sung-Min,an heir to his father's company YSM.At first they don't get along,but she put their differences aside and got to know each other more.