Monroe Timmy is a light orange fish with black eyes. He wears a blue and yellow propeller cap in the episode, "Krabby Land," and a red and green propeller cap in "The Sponge Who Could Fly." He wears lime green pants with a black belt, with a gold colored belt buckle. In some episodes, he appears to be green.
He does not like pistachio ice cream, but it's shown that he asks for it, as seen in the episode "Hocus Pocus."
He seems to enjoy SpongeBob's pain and agony during the episode, "Krabby Land," but near the end, he called SpongeBob, "Mr. SquarePants," a possible show of respect to SpongeBob himself. In the first movie, he is red with woman eyebrows and light green shorts.