The Life of SpongeBob SquarePants/Universe/Characters

Main:

 * SpongeBob SquarePants, protagonist of the series, extremely-skilled fry cook at the Krusty Krab
 * Patrick Star, deuteragonist of the series, SpongeBob's dim-witted yet fiercely loyal best friend
 * Squidward Tentacles, tritagonist of the series, despises SpongeBob, Patrick, and Mr. Krabs most of them and desires to get out of his job as Krusty Krab cashier, but will do anything to get them out of grave danger
 * Eugene H. Krabs, owner and operator of the Krusty Krab, employer of SpongeBob and Squidward, shrewd and very capable businessman who brought the Krusty Krab to glory, but also extremely greedy, unscrupulous, and manipulative

Major background:

 * Fred, brown fish, married to Sadie Rechid, Bikini Bottom citizen, Krusty Krab regular customer
 * Sadie Rechid, orange and tan fish, married to Fred, Bikini Bottom citizen, Krusty Krab regular customer
 * Nat Peterson, yellow tan fish with a purple fin, Bikini Bottom citizen, Krusty Krab regular customer
 * Harold "Bill" Reginald, blue fish with white shirt and red Speedo, Bikini Bottom citizen, Krusty Krab regular customer
 * Old Man Jenkins, elderly Bikini Bottom citizen, skinny with gray skin, Krusty Krab regular customer

Other

 * Gustav Savalas, doctor at the Bikini Bottom General Hospital, zealous defender of the hospital's policies