Her husband, who is much older than her, has a lukewarm nightlife, leaving his wife, Reiko, frustrated. Though he is her son, he is a stepchild and a complete stranger. In front of this young man, Reiko, the stepmother, is no longer able to suppress her desires. Her sexual desires run wild, and she even makes a move on her son's friends. Controlled by her intense sexual desire, the stepmother has lost all sense of ethics and continues to desire her son, ignoring the idea of incest...