Incidental 18 is a character in the series who makes several cameo appearances. He is a resident of Bikini Bottom.
He is a short, light olive green fish with red-orange dots and lips. He wears square shaped nerd glasses and black shoes.
His first appearance was in the episode "Ripped Pants." His second appearance was in the episode "Plankton!" He appears in "Pickles" at the Krusty Krab again in the background several times. He briefly appears in "Suds" in the Krusty Krab again when Mr. Krabs said, "I just can't have you sneezing all over my food!" he is shocked and disgusted and runs out of the Krusty Krab along with the other customers.