He is a dark green worm with light yellow-green and black eyes. He has a black leash with metal bolts on it.
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. Mr. Krabs also takes him to walk like how pet owners take their dogs to walks.
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 where the Krusty Krab commercial is being shot. His name is revealed in this episode.
What's Your Bikini Bottom Pet?
He is one of the pets featured on the title screen in this online game.