Minamoto Taiyo is an 18-year-old who devotes himself to baseball in the hopes of winning the heart of his idol, Maekawa Fumie. However, despite his talent, he fails the pro test due to his tendency to get too worked up. Then he receives an invitation to try out for amateur baseball. Taiyo's fastball skills are appreciated, and he joins Iruka-ya, a large supermarket chain, and he enters the world of amateur baseball. However, just as he is about to do so, suspicions of a romantic relationship emerge. The man in question is Akune Mitsuo, who hit five home runs at Koshien and is known by the public as a monster...!?