Main article: List of characters in SpongeBob SquarePants SpongeBob SquarePants main characters (from left to right): Plankton, Mr. Krabs, Sandy, SpongeBob, Squidward, Patrick, and Gary. SpongeBob SquarePants is an extremely energetic and optimistic sea sponge (although his appearance more closely resembles a kitchen sponge ) who lives in a pineapple under the