Married to her earnest and kind husband whom she had been in a relationship with since her college days, Sumire is a married woman who feels happy with her everyday life as a married couple. However, her life is turned upside down by her husband's boss. While her husband is away, the boss takes advantage of his position and forces his swollen, veiny cock into Sumire. Sumire is given pleasure she has never felt with her husband, and gradually her resistance weakens, and she begins to seek pleasure and cock herself.