Kazuto Tonoma is the second baseman for the Meikun High School baseball team. He belongs to the "Yamada generation" alongside teammates Taro Yamada, Masami Iwaki, and Satoru Satonaka. This group transfers from Takaoka Middle School to Meikun High School in Volume 8 of the original manga. Tonoma is consistently recognized as one of the team's "Four Heavenly Kings."