Kenji is a short, virgin boy who is not popular with women, but he is in the midst of puberty and has a stronger sexual desire than most. He is walking around feeling horny when he sees a pornographic flyer on the roadside and calls a delivery health service from a public phone. Kyoko Hanamiya, who is super tall at 195cm, shows up. The huge height difference and the sweet older sister who pampers him and makes him have sex with her make him happy.