Portnoy is a character in Berke Breathed's comic strip Bloom County. Portnoy was one of the critters that could talk, and was often surly mouthed and bigoted, usually leading Hodge-Podge, his best friend, to have to cover his mouth. When Bill the Cat became a televangelist denouncing "penguin lust", Portnoy helped run Opus the penguin out of town. The character was named for Portnoy's Complaint, a novel about sexual frustration.
Portnoy changed physically over the years; sometimes into an entirely different animal. It was initially unknown what species he was; sometimes a squirrel, a possum, or a . Finally he was revealed as a groundhog, which he had hidden because Hodge didn't associate with "pigs". Eventually the two made up.
Portnoy and Hodge enjoy human-like entertainment, such as strip bars and playing jokes on others (Portnoy once pretended to be stuffed).