Muttley is a German Shepherd with tan fur and a black muzzle. He has blue eyes. He wears a black fedora with a white band on it to make it similar to Kitty's hair. He wears a long sleeved shirt with a blue tie underneath a buttoned gray jacket. He wears white gloves, a belt, dark blue jeans, and white boots. He will be voiced by Tom Kenny.
- He is the species that everyone thinks is the opposite of cats: dogs.
- Like Kitty, he is bad at dancing.
- It is revealed that Muttley's favorite color is blue.