Bob McCarthy is a 27-year old prison officer. He saw closely the fierce fight between Baki and Oliva. He observes the fight until the end even being astonished by both fighters.
Like the rest of the Arizona prison police, he shows great fear of Biscuit Oliva and Baki Hanma. He also has a great memory, being able to remember exact moments of his childhood.
(Source: Baki Wiki)