He is a dark green worm with light yellow-green and black eyes. He has a black leash.
Mr. Doodles, like all worms, is an underwater equivalent of a dog, as snails are those to cats. He is not shown to be vicious like guard worms; he just likes to bark and be walked by his owner. He is a good companion to have, as shown in "As Seen on TV" like how all worms are to their fish owners. He likes to smell things, as most real-world dogs do.
Role in series
He is one of the characters who gets trapped in a moon rock sack by SpongeBob and Patrick.
"As Seen on TV"
Mr. Krabs walks him to work. His name is revealed and it is shown that he enjoys sniffing things and taking walks.