Hitozuma maru-ura tōsatsu: Haitoku no jōkō

Original title: 人妻(裏)盗撮　背徳の情交

Reiji, a young man who single-handedly runs an electrical shop inherited from his parents, has a hobby of secretly installing small cameras while repairing appliances and spying on other people's private lives. He then sells the footage to illegal businesses. One day, Reiji falls in love at first sight with Yoko, a married woman who comes in to change a light bulb.