Masami, an ordinary housewife, lives with her husband Kenji, who suffers from sexual dysfunction. As a result, their sex life has dwindled, and she takes her sexual frustration out on him. One day, Kenji's former boss, Oshima, visits. Oshima reveals that Kenji left behind a debt and demands that Masami repay it with her body, eventually crossing the line. While overwhelmed with guilt, Masami finds herself writhing in pleasure from Oshima's sexual play.