Reina, a mother, comes to the house of her only daughter Manami, who got married three years ago. Her daughter asks her to mediate the relationship between her and her husband, who has cooled off, and Reina comforts her husband, Tooru, who is tired from work. Tooru is touched by the kindness of his beautiful stepmother and is at the mercy of Reina's charms... Tooru finds himself seeking his attractive stepmother more than his wife, and is unable to suppress the sexual desires that arise from their forbidden relationship...