Sachiko Nishio, daughter of Meisei High’s baseball coach Shigenori Nishio, serves as the team’s dedicated manager. She forms a supportive bond with Minami Asakura, encouraging her to embrace a managerial role. As the girlfriend of former ace pitcher Takeshi Kuroki, Sachiko collaborates with him to scout promising talent, leading them to recognize the potential of Tatsuya Uesugi—older brother of Kazuya Uesugi—whom they strive to recruit for Meisei’s baseball program. Her role revolves around strengthening recruitment efforts and cultivating pivotal connections, particularly with Minami, to reinforce the team’s dynamics.