An ordinary married couple in their second year of marriage. One day, the husband's younger brother comes to Tokyo. The two begin to take an interest in each other and are drawn to each other. The husband is sexually impotent, so the wife's desires are building up and she finally enters into a forbidden relationship. The wife is toyed with day and night by sexual techniques she has never experienced before, and her carnal instincts are awakened. Although she pretends to be faithful in front of her husband...