In April 2018, a female student joins the baseball club of Tochigi Prefectural Kanuma High School. Her name is Kawase Haruka. Haruka, who joined the club as a player instead of a manager, was the only female player in the prefecture for three years, even though her best friend Mogi Mayu asked her to "go home and enjoy her JK life". She works hard with boys to practice hard. Haruka's position is the same as her classmate Sonoda Harumichi. Haruka does not make excuses for her physical strength and physique, and strives to acquire the same skills as boys, but no matter how much she improves, she has one thing that Haruka cannot do like boys. It is to dream of "Koshien". This is because there is a strict rule that female players cannot participate in official games in high school baseball. In 2020, shocking news hits Haruka and others who are in the third grade. The first Koshien tournament after the war was canceled due to Corona. Sonoda and his friends, who have lost their goals, lose the energy to hold the bat. However, even in such a case, Haruka continues to practice independently. Sonoda and his friends, who first understood the situation of Haruka who couldn't even have the goal of playing in the match, let alone Koshien, want to make Haruka on the stage of the official match even if she exceed the rules.