Widow Rei, unable to overcome the loss of her husband, succumbs to loneliness one day and confesses her feelings to her son, who resembles her late husband. She chooses to become intimate with him, believing it to be just a single night. However, her son does not see it that way. Experiencing a woman's body for the first time, he becomes intensely drawn to Rei. Unable to resist, she gives in, gradually being consumed by forbidden emotions and pulled into a deep whirlpool of desire.