Mitsu is a girl who dedicated her youth to the junior high school track team; however, she retires after suffering from an injury. One day, her bag, which she dearly treasured, fell onto the train tracks. A boy then suddenly risks his life to retrieve her bag. Having missed her chance to say thank you, she finally meets him again in high school. Despite her efforts to thank him, the boy constantly gives Mitsu the cold shoulder… This is a love story about an honest, straightforward girl and a cold, popular boy.

Hibari, a high school student, is actually going out with the biology teacher, Aoi. A love between a teacher and student must be kept a secret! Mail, phone, dates, kisses…anything lover-like are all banned! It's a relationship where they will break up if there's even a rumor about them. Because of that, the feelings of love must be protected… It is a pure and restricted love with the serious biology teacher, the love of a heart throbbing every day will begin! Pt/Br: Hibari, uma estudante do ensino médio, está saindo com seu professor de biologia, Aoi. Um amor entre professor e aluna que deve ser mantido em segredo! Cartas, telefonemas, encontros, beijos… qualquer coisa que se pareça com um relacionamento está banido! É um relacionamento que terminará se houver algum boato sobre eles. Por isso, os sentimentos de amor devem ser protegidos… É um amor puro e restrito com a professora de biologia; o amor de um coração pulsando todos os dias começará!