During a visit to her late mother-in-law's grave, Haruka returns to her father-in-law's solitary home. That night, he witnesses his son and daughter-in-law's private moment, leaving him frustrated and filled with resentment toward his unsatisfied son. The next day, while Haruka is cleaning the room, her father-in-law tempts her, claiming he can make her climax repeatedly. Initially resisting, Haruka gradually finds her heart swayed as the sexually insatiable father-in-law brings her to orgasm after orgasm. Confused by his passionate advances, her emotions begin to waver. Her relationship with her father-in-law slowly grows deeper.