Mitsune Kokura is 50 years old and a mother of two. Since she quit her job and got married, she has been living peacefully as a full-time housewife for 22 years. A faithful wife who loves her children - that's what makes a woman happy. "There was a time when I felt the same way," she says. Her husband, who is 10 years older, has recently experienced a marked decline in his interest in sex. Mitsunori had thought that after she retired, the children would live independently and they would have more time alone, but that feeling changed when the word 'infidelity' first came to her mind. She wrestles with whether she's thinking about taboos and tries to reassure herself, but the answer is there the moment she realizes that her husband is completely finished as a man. A beautiful, elegant wife in her fifties prepares for the first infidelity of her life.