Hye-ran, who has been living alone, has to live with Sang-woo, the nephew of her stepfather who her mother remarried. As time went, Hye-ran begins to feel lust whenever she sees Sang-woo. Even without blood relations, Hye-ran is confused about her feelings for Sang-woo, and she is also certain that her boyfriend, Gi-joon, is involved with another woman. Meanwhile, Sang-woo who had sex with Ji-eun, confessed to her that he was thinking of Hye-ran when they were in the middle of doing it, and then announced their breakup. Sang-woo went home late that night. Upon arriving the house, Sang-woo found Hye-ran in her underwear, pretending to sleep. Sang-woo eventually went in and touched Hye-ran. After confirming how much he wants her, she let Sang-woo take over her body.

4수생 석진은 시험 성적표를 아버지에게 보여준다. 그런데 형편없는 성적에 화가 난 아버지는 아들에게 “이번에도 대학 못 가면 군대 보내겠다” 라며 개인 과외를 제안한다. 과외 첫날부터 젊고 섹시한 여자 선생님이 오고, 국영수 모든 과목 선생님이 여자다. 문제를 풀면 원하는 걸 다 해주겠다는 약속으로 열심히 공부하는데…, 매일 과외 시간이 행복한 석진은 대학을 갈수 있을까?

Jeong-goo is in a relationship with his son's girlfriend, Mi-hee. Mi-hee feels guilty and breaks up with Yeong-jin, and Yeong-jin who is struggling because of it, got in a relationship with Joo-eun. Yeong-jin's ex-wife, Yeon-ri meets Jeong-goo by chance and finds out about the whole thing, and Yeon-ri who was curious about Jeong-goo, sleeps with him...