Billy is a kid who appears as the second main antagonist in the episode "Friend or Foe."
He is a light purple kid fish with faded blue lips and wears a red shirt and a white and blue cap.
He is the leader of a group of class bullies at Poseidon Elementary School who constantly make fun of Mr. Krabs about his clothes, and call him "Rag Boy" and also bully Plankton for his small size and brilliant intelligence, as well as the fact that he is friends with Mr. Krabs, or "Rag Boy." He appears in "The Clash of Triton" as a baseball player at the Baseball Field. He also appears in other episodes as a background character. He also appears in "Don't Look Now" as one of the kids that was in the film.
He is the first child bully to be shown in the series.