After school, Akira Sakagami is about to ask his classmate, Nana Shirayuki out on a date. It was good until she called out to him, but he was interrupted by the appearance of his sister Rio.<br> For Akira, Rio is not only his sister but also his first love. Rio used to live alone, but due to a housing situation, she has now returned to her parents house with Akira. When Akira is told by Rio that Shirayuki looks like her, he sees Shirayuki and Rio in her.<br> That night, Akira is seen masturbating by Rio. While Akira is frozen in place, Rio is unfazed and makes fun of the actress he was using as a joke, saying she looks like her. Not only that, but she also grabbed Akira's thing.