A beautiful, stylish mother named Honami, still young and attractive, lives with her husband constantly away on business, leaving her sexually unfulfilled. To cope with her intense desires, she secretly pleases herself. Her son, Masaru, begins to notice his mother's growing feminine sensuality and gradually starts seeing her as a woman. One day, he steals her damp underwear and starts masturbating while inhaling its scent. Furious at her son's shameless act, Honami spanks his buttocks, but through this act of punishment, an uncontrollable lust begins to awaken deep within her.