Ryo, a newly married man, lives with his mother-in-law Sayoko because his husband is away on a business trip. The two get along well, but Sayoko begins to have special feelings for Ryo. One day, unable to bear the loneliness, Ryo starts masturbating in his bedroom. Sayoko peeks at him and masturbates herself. The next day, Sayoko can no longer contain her feelings and directs her twisted love towards Ryo.