The sister-in-law's erotic body arouses the brother's desire!! A couple living in Tokyo is alone one day with the wife's sister who came to Tokyo from the countryside... The wife is hospitalized, and the sister-in-law comes to help with the housework... The sister-in-law is an office worker working in Tokyo, and she always seems tired, so she gives her a massage... The brother-in-law comes on to her, and she can't refuse, so they have an incestuous fuck!!