Ki-joon and Su-mi, who have been married for 3 years. Except for the newlyweds, the couple quarreled almost every day. Criteria for wanting a child and Sumi not wanting a child. Because he likes alcohol and friends, he gets home late every day, because of Ki-joon's unique sexual orientation. In her second year of marriage, Ki-joon confesses that she wants to have a two-to-one threesome as her birthday present, and the two get divorced. After her divorce, Ki-joon remarries with a young and innocent Yeon-ji, and her ex-wife, Su-mi, comes into Ki-joon's house and starts living together in a dizzying way...