For more info on Mordecai, check out his article on the Regular Show Wiki

Mordecai character
Gender Male
Occupation Groundskeeper
Relationships Rigby (best friend)
Voiced by J.G. Quintel
Mordecai is one of the main protagonists of Regular Show, along with his best friend Rigby. Mordecai is a 23-year old Blue Jay. He made his debut in a non-canon short (2 in the AM PM) as a human cashier, who then morphs into a prototype Mordecai-like character with a fanny pack. He later makes his first official appearance in the Pilot episode. Mordecai is voiced by the show's creator, J.G. Quintel.