Kozue, who lives with her husband and daughter and son-in-law, spends a night alone with her son-in-law, Masahiro, one day. In his drunken state, Masahiro confesses his love for Kozue and his hidden desires explode! "It's a waste to leave my mother-in-law's body alone!" Kozue is flustered by the immoral act, but her sexless body feels the pleasure of being violated by her son-in-law.