Eugene H. Krabs is the penny-pinching owner and founder of The Krusty Krab, a fast food restaurant in Bikini Bottom. He sometimes identifies himself as a sailor, most likely because he did serve in the Navy at one point (earning the nickname Armor Abs Krabs). During his service, he was the chief janitor on the S.S. Gourmet and "head chef" on the "S.S. Diarrhea" (figure of speech, since he cleaned the bathrooms). Sometimes when he appears onscreen, sailor's music is played; Krabs uses sea-faring vocabulary; he calls disagreement mutiny and calls the bathroom the head while his laugh is akin to those of sailors. In contrast to his namesake, Krabs is something of a miser; he is known to go insane if he has to give up so much as a penny. In "Born Again Krabs", he gave SpongeBob up to the Flying Dutchman for sixty-two cents, but repented later. Much of the comic relief of his character is due to his enormous love of money. When customers leave the restaurant because they don't like the food (which is usually due to SpongeBob or Squidward's innaccuracies), he uses catchphrases - these include "That's me money walkin' out the door!", or "There's gonna be a few changes around here!" In "Culture Shock", he even stole SpongeBob's one-cent tip.
However, he's a caring and thoughtful crab; he appreciates his employees, SpongeBob SquarePants and Squidward Tentacles (except for in the episode "Have You Seen This Snail?" where he was extremely unsympathetic when SpongeBob told him that he lost Gary), dotes on his daughter, Pearl Krabs, and in one episode, he found his second love (after money), Mrs. Puff (in "Krusty Love"). Mr. Krabs' arch-rival is Sheldon J. Plankton, the owner of rival restaurant The Chum Bucket across the street from his establishment. He has a mother, Mama Krabs, who lives in a near identical version of his anchor home, except it is pink. Krabs' birthday, revealed on his driver's license in the episode "Sleepy Time", is November 30, 1942. His address was also revealed to be 3541 Anchor Way. Krabs served in the Navy, where he earned the nickname "Armor Abs Krabs". Mr. Krabs tries to keep it cheap, when purchasing anything, even though he's the richest crab in the ocean, which often results in Pearl becoming extremely disappointed in her gifts, such as on her 16th birthday or the infamous squeaky boots.
Ever since he was a young child, Eugene H. Krabs has always been a penny-pinching financial genius, like he is in the present day. In the episode "My Pretty Seahorse", Mr. Krabs told SpongeBob of a story about his father giving him a dollar at the age of five years old. He recalls that he loved that dollar like a brother; however, he spent it on a soda, one hot day at the beach.
After a war, Krabs stay secluded in a deep depression that seemed endless. His luck changed when he bought a local (failing) retirement home, "The Rusty Crab," which he decided to turn into a restaurant, adding a K to "Rusty" and replacing the C with a K ("Krab"). He decided to go into business selling his family's Krabby Patty burger. It was revealed to be a family secret in "Enemy In-Law." and it was King Krabs who named the burger, back in the Middle Ages. In 1959, a chum famine wiped out all of the chum crops, causing Krabs to give breaks to his employees.
Mr. Krabs served in the navy, at an unknown age. He worked as the janitor on the S.S. Gourmet and the head chef of the S.S. Diarrhea.
The Krusty Krab has come close to going out of business due to such rival restaurants as the aforementioned Chum Bucket, Pretty Patties, and The Shell Shack just to name a few. The building is also in serious disrepair, as its walls ooze green slime, and it has seriously faulty electrical wiring. Mr. Krabs idea of maintenance is to simply place bandages on cracks in the walls, which obviously is inadequate.
An Olympics-type sporting event was started about 1981, the Fry Cook Games. Krabs competed against his arch rival, Sheldon J. Plankton. Mr. Krabs won gold for a challenge by lifting a pickles-dumbell, however lost to Plankton in the Onion-Ring Routine.
In the movie, Krabs opened The Krusty Krab 2, right next to the original burger stand, where Squidward is chosen to be the manager (much to SpongeBob's dismay).
It is likely that he is a descendant of the Krabs family of prehistoric times who constantly repeat the word "Money".
Krabs appears in "Lights, Camera, PANTS!" In the PC version, in his office in the Krusty Krab, he can't count his money anymore and a doctor is there to assist. SpongeBob uses the Golden Spatula to make the Royal Krabby Patty. Krabs eats it and can now count the money. His role in the special episode of "The New Adventures of Mermaid Man and Barnacle Boy" is that of a news reporter.
- In the episode where SpongeBob is being stalked by the Tattletale Strangler, SpongeBob asks Mr. Krabs to be his bodyguard. Mr. Krabs then goes on to brag about being a 5 time golden claws winner in the Navy.
- In the SpongeBob SquarePants: Lights, Camera, Pants! video game website, Mr. Krabs' full name is Eugene V. Krabs instead of Eugene H. Krabs
- He hates golf.