Furrball

Furrball (voiced by Frank Welker) is a young, blue male cat with a hole on his right ear and a bandage on his tail. Furrball is usually depicted as living in a cardboard box in an alleyway, although other times he is shown as one of Elmyra's pets and briefly had a home with Mary Melody. He is often a quite peaceful and innocent character, but he is also one of the most unfortunate characters in the show, since he is almost always chased, abused or bullied, often by being squashed. For example, during the intro credits, he gets flattened by a falling piano along with the lyric "Furrball's unlucky". He is less anthropomorphic in nature than the other animal characters, generally walking on all fours and almost always a mute, except for typical cat sounds.

He is based on Sylvester[6] and often chases Sweetie Pie, who is based on Tweety. Unlike Sylvester, Furrball rarely speaks and therefore mostly resembles the Sylvester of the Chuck Jones cartoons, who is silent. In one speaking role (Cinemaniacs), he was voiced by Rob Paulsen in a mockup of Leonard McCoy from Star Trek.