Description：Lee Won-seo (Kim Jung-gyun), a father with cerebral palsy, and his daughter Lee Jer-ruo (Oh Ye-seol) live together on Ganghwa Island. Lee Won-seo is excited that his daughter has been admitted to the Noble Arts High School in Seoul, and happily moves to Seoul with his daughter. Unexpectedly, the nightmare begins. Jer-ruo grew up in the choir and has a high vocal range, so she quickly stood out in school, and was envied by her female classmates, led by Hye-sun. Jer-ruo is strong and competitive, and resists school violence, but is constantly hit back more cruelly. In the end, she can't stand the endless torture and commits suicide. In order to find out the truth of the matter, father Won-seo seeks justice in all walks of life, but this society ignores the groans of the weak, so Won-seo decides to punish those who bullied his daughter in his own way.