Son Chaeyoung had been smiling and full of dreams at her young age but losing her mother a year ago had change her life.... Everyone around her had noticed the drastic change.... But then an accident happened making her almost lose her life... she was save by a woman....the woman died instead of her not knowing that the woman who save her life is Chou Sally's mother, her transferee classmate... But who is Chou Sally's mother? The thing that