Shiina Kanako, voted the most beautiful girl in her high school, is a member of the school's gymnastics team. Overhearing talk that the boy's soccer team was planning to harass her team during summer training, Shiina decides to ask a mysterious group on campus called "Trouble Dog" rumored to solve all sorts of clients' problems for money. Through this she encounters three mysterious guys named Ryuu, Pochi, and Sabu. Who are they really and what do they want her to do?