She is a sperm whale, which means her mother was most likely a whale as well. She is revealed to be sixteen years old in the episode "Whale of a Birthday."
She is shown to be an extremely spoiled, entitled, selfish and insolent teenage girl, often demanding things (usually money) from her father and throwing tantrums whenever they are not met. Her ill-mannered nature is likely due to Mr. Krabs' poor parenting, him being too lenient on her and giving in to whatever she demands.
In "Selling Out," Pearl can be seen as a baby in a scrapbook. Mr. Krabs was holding her in the picture, so it is possible that he could have taken her. In another photo, Pearl can be seen riding a bike as a toddler with the guidance of Mr. Krabs.
Pearl is seen wearing a short pink cheerleader dress, with a P stitched into it which stands for Pearl. She also sports short, white, heeled boots. Pearl has smooth gray skin and is huge. When she cries, she floods the area. Pearl has a red heart lipstick on her nose that turns into lips when she kisses, and she has blonde hair pulled into a ponytail with a pink clip. She has blue eyes and six eyelashes on each eye.
This section contains speculative information. This information has not been confirmed. Please keep this in mind.
Mr. Krabs is Pearl's father, and as such, Mr. Krabs is in nearly every episode that features her. She is often very disrespectful towards him, using him as a source of money. Despite realizing this, Mr. Krabs never tells her off, even allowing her to force him to meet her demands.
Despite their troubled relationship and conflicting traits, they love each other very much and share a close bond.
It is possible that she is adopted or that Mr. Krabs' wife was a whale. This theory could be disputed since it is shown in "Dunces and Dragons" that whales have existed in the Krabs family for centuries.
Although Pearl has been seen with her father many times throughout the series, she has not yet been seen onscreen with her grandmother, Betsy Krabs, unless you count Mr. Krabs' thought of his funeral in "Lame and Fortune."
In the past, Pearl has appeared to like SpongeBob. In "The Chaperone," she takes him to the prom and ends up enjoying her time, despite the trouble SpongeBob causes. In "The Slumber Party," Pearl acts annoyed towards SpongeBob, possibly because she thinks that he is helping Mr. Krabs. In "Barnacle Face," she thanks SpongeBob for allowing her to go to the school dance when he puts diamonds on her face. In some episodes, they display a like/hate relationship.
While they have seen each other before, they have yet to interact properly. Pearl knows Patrick, but they are not friends. Patrick ate one of Pearl's Krabby Patties in "Welcome to the Bikini Bottom Triangle," but he doesn't like them as much as SpongeBob's. In the episode "Tunnel of Glove," he tried to get SpongeBob and Pearl out of the Tunnel of Glove, which they were stuck in.
Sandy and Pearl have not had much interaction, but they have encountered one another. In "Bubble Troubles," Pearl helps Sandy by giving her air. They seem to share a mutual friendship, as Pearl believes that mammals need to stick together. At the beginning of the episode "Mr. Krabs Takes a Vacation," Sandy was seen sitting directly in front of Pearl while Mr. Krabs was getting everyone (except Squidward) excited about the story of the vacation trip. In "Texas," Pearl was one of the townspeople who wanted Sandy to stay in Bikini Bottom. She and the rest cheered for Sandy that she decides to stay in Bikini Bottom.
Squidward and Pearl have an awkward relationship. In "The Chaperone," Pearl refuses to go out with him to her prom. In "Welcome to the Bikini Bottom Triangle," Squidward calls her a "drama queen." Pearl thinks that Squidward is such a "barnacle." She likes teasing him (as seen in "Drive Thru").
Friends in Bikini Bottom High
Pearl and her friends were best friends, in "The Chaperone," they didn't laugh at Pearl that SpongeBob is her prom date, then in Tunnel of Glove, they teased and humiliated Pearl that SpongeBob is her boyfriend, then they told the whole TV broadcast that Pearl and SpongeBob are dating. Then in "Drive Thru," Pearl had new friends. It is possible she got new friends because her old friends made fun of her.
"Oh, actually it was really funny when that hot dog landed in Judy's hair!" —"The Chaperone"
"Daddy! I'm borrowing your wallet! Line dancing? Ewww, that is so lame. What they need is my way cool cheer routine." ("Tentacle-Vision")
"Dad, you've ruined me!" ("Squeaky Boots")
Pearl and Sandy are the only major characters who are mammals.
Currently, she has only appeared in one episode ("Tunnel of Glove") without Mr. Krabs.
Pearl becomes more spoiled and rude in later episodes, possibly due to the cheapness of her father. In the episode "Selling Out," she was extremely rude to Mr. Krabs for wanting to spend time with her even though he did nothing wrong. In "Welcome to the Bikini Bottom Triangle," she demands to go to the mall, even though she should be concerned that she is trapped on a deserted island.
Since Pearl is a whale, and mammals have lungs, she needs air to breathe. It is revealed in "Bubble Troubles" that she holds air in her nose to breathe when underwater.