The movie revolves around Eun-sook (Moon So-ri), a lovely but promiscuous professor in a university, who has all the male professors wrapped around her finger. When a popular comic book artist Seok-gyu (Ji Jin-hee) joins the environmental awareness group that she belongs to, he attracts the jealously of Mr. Yoo, a group member who fears that he would steal Eun-sook from him, even though Eun-sook does not return his intense love. What is not known to the rest is that Eun-sook and Seok-gyu attended the same junior high school where they share a secretive tragic history. Back then, Eun-sook was the girlfriend of Seok-gyu’s older brother and the three rebellious teenagers indulged in promiscuous sex . Eun-sook worries that her past may be revealed.