Kun-woo was once a promising Taekwondo player but quit after appealing the judge's wrong and unjust call. On the first day of school, he somehow gets involved in a big fight between the school thugs, defeating all of them. Rumors about him spread fast, and every thug in the school challenges him and loses. As the series of fights go on, Kun-woo finds a thing he can enjoy in his miserable life.