Kaoru Kishimoto

Kaio Middle School Go club president and former insei who did not become a professional. He played Akira in a game, and had to resign early and admitted he was outclassed and right not to pursue professional play. Later he plays a match against Hikaru to gauge his strength, and defeats him easily. His dismissive attitude to Hikaru's plan to rise to Akira's level while playing in the school club spurs Hikaru on to register as an insei. His liking for black coffee allows Hikaru to realize that he is the failed insei that the other insei are discussing shortly after Hikaru becomes an insei.

(Source: Wikipedia)