Michio Shirakwa (白川七段 Shirakawa Michio) a.k.a. Shirakawa Sensei (白川先生) - A 7-dan Go player and the community Go leader. He was mentored by Morishita. A member of Morishita's study group and a community go teacher.
He is a gentle and easy-going teacher.
Shirakawa first appear where he teaches a go class at a community center where Hikaru attend
Internet Go Arc
He has a real-life "Avatar". Ishikura Noboru says in one of his books that this character was based on him.