Who does retro bill play off of SpongeBob?

Retro Bill is a character from the children's entertainment world and is not directly associated with SpongeBob SquarePants. He is known for promoting safety and positive messages to kids, often through engaging performances. In contrast, SpongeBob SquarePants features a variety of characters, with SpongeBob himself embodying an optimistic and goofy personality. If you're referencing a specific episode or crossover, please provide more details!