hobnobber

colleague, coworker, equal, peer, workmate

accomplice, affiliate, ally, collaborator, confederate, half, partner

buddy, chum, confidant, familiar, friend, hearty, intimate, pal

countryman

classmate, housemate, messmate, playfellow, playmate, roommate (also roomie), schoolmate, shipmate, teammate

attendant, escort

hanger-on, leech, parasite