In the beautiful prefecture of Kami River, there is a girl named Aoi Mizuhoho (18) attending a public high school. She has been dating her classmate Shou, whom she met at their school. They are both each other's first boyfriend/girlfriend. Unlike most students, Mizuhoho isn't very noticeable or popular among her peers. After two months of being together, they decide to have sex for the first time at Shou's house. Note that the contents may vary depending on the recording method used.