“I must get into that school!”That was the sudden thought Chinatsu had during the summer of her third year in middle school. Chinatsu never really thought about her goals and dreams in life, but after seeing a match in the Japan National High School Baseball Tournament (or Koushien), she suddenly had a goal to achieve! She worked extra hard, and finally got into the school, but on the first day, she meets a fierce looking senpai who is actually the baseball team's ace player! Once again, Chinatsu did her best and managed to be the baseball team's manager, yet the most important player is...?!