Kang Seul Woo is a famous soccer player at his school. He is known to be his school's superstar. Even so, he had always has a problem with Jongin, a senior in his school. Jongin never liked Seul Woo ever since Seul Woo accidentally kicked him during soccer practice.

One day, Jongin found Seul Woo dressed up as a girl. Seul Woo then admitted that he was actually a girl disguised as a boy. Out of sympathy, Jongin slowly protect him from other boys during soccer practice.

One thing he did not know, Kang Seul Woo actually has a naughty twin sister, Kang Seul Gi.