Ryosuke failed the university entrance exam and is now a repeat student. Worried about Ryosuke, his father decides to ask Maki, the wife of an acquaintance and a talented private tutor, to help Ryosuke with his studies. Ryosuke wants to pass next year, but he can't help but be interested in Maki's sexy chest... Maki notices this and gives Ryosuke a naughty reward every time he solves a problem, leading him to pass the university entrance exam.