ROYD-199 姊姊長相樸素、謙虛，但摘下眼鏡後卻是絕色美人。我無法抗拒，走近了她，她用裸露的陰莖給了我第一次內射。西野惠美

The plain sister-in-law has been transformed! With the advice of her brother-in-law, she has become a beautiful woman that everyone turns their heads to see! However, the brother has always liked her... He decides to confess his feelings to her before someone else steals her away! He expresses his feelings, but she rejects him because they are brother and sister. The brother says, "We don't have to put it in, just rub it together..." and they only promised to do a bare thigh job, but of course it doesn't end there... Once they do it, it doesn't end there, and they do it over and over again... The sister-in-law gradually becomes attracted to her brother...