Dr. Fisby is a cat who debuted in the episode “Cat Fever”. As his title indicates, Fisby is a doctor who cares for sick cats and ensure they feel better.
Fisby has reddish-brown fur, navy blue eyes, blue glasses, and large dark brown eyebrows and mustache. Along with his sky-blue collared shirt and red tie, he typically wears attire relating to his profession which consists of a head mirror, white lab coat, and stethoscope.
Fisby's voice actor Henry F. Benjamin also voices Boss.