The story tells about a handsome male student, Lee Daeyeol, who moved to Woollim High with his family after his parents announced that their company transferred them to Mapo-gu to be in charge of a new branch of a famous restaurant and also he wanted to get away from his ex-crush and also his ex-girlfriend who is obsessed with him. His elder brother and one of the most kind senior, Lee Sungyeol, had studied there before his family moved there. Thanks to his impressive examination marks, he had studied there earlier and lived in the dorm before officially living with his family. Daeyeol's first day of school doesn't go quite well. He meets with Ko Hyun-kyung, who is known as 'The Girl with Red Ribbon Hair Band', is the sole, superior bully of Woollim High who is portrayed as a heartless, cruel and merciless female bully of Woollim High. Everyone is her victim and Daeyeol is no exception. She hurts Daeyeol awfully every day and Daeyeol, on the other hand, wants to be friends with her and determines to make that dream come true despite getting hurt non-stop. Daeyeol soon encounters the secret beneath Hyun-kyung's red ribbon hair band which she wears it to school every day.