Nao is a young married student who gave birth soon after getting married and is attending university while raising her child. Nao is introduced by the university to be a private tutor for Yoshioka, a student studying for entrance exams who lives next door to her in the same apartment building. Nao has a serious and cheerful personality, but she is weak to pressure and can't say no. Yoshioka sometimes tries to gain Nao's sympathy, and sometimes uses the exam to somehow give up his virginity! Nao, who has a husband and child, desperately resists, but after giving birth, her frustrated body gradually gives in to the young student's momentum...