Suna no ue no shokubutsu-gun

Seller Ichiro gets a sexual invitation from an unknown girl. She has sex with him to physically hurt her sister, Kyoko, who attends hotels with men in broad daylight. Intrigued, Ichiro goes behind Kyoko and is immediately immersed in a non-natural relationship by sexual desire masochistic Kyoko. (fjsp.org.br) (Summary by storyoftheye)