Hisae, bound by a deep connection that transcends the ordinary mother-son relationship, always acted strictly toward her son in front of her husband, hiding his bizarre behavior. After her husband's death, she became abnormally overprotective, developing an intense interest in her son's private life. From morning on, she stimulates his penis with tongue kisses, finding pleasure in sucking him off and drawing out his semen. When her son masturbates, she joins him as an erotic model, sharing in the act. Their bond deepens in the bath and bed, as she increasingly seeks to monopolize every part of him.