After losing her husband in an accidental death, Mako Oda finds her stepson Satoshi withdrawing into himself from the trauma of losing his father. Struggling to support him through part-time work at home, her hardships go unnoticed by Satoshi. One night, after accidentally watching an adult video, Satoshi devises a devilish plan. Mako, crossing the boundary of her role as a stepmother, gradually succumbs to her stepson's demands, leading their relationship into uncharted territory. The film's appeal is heightened by Ayano Kato's compelling performance in a full creampie milf storyline.