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Jimbo wears a purple knit cap (originally no knit cap), a black short-sleeved T-shirt, emblazoned with a menacing skull (originally, a yellow short-sleeved suit), blue jeans, and black shoes. Bart describes him as a good looking rebel who plays by his own rules.
A real low-life, Jimbo is generally acknowledged as the leader of the bully gang. Jimbo can often be seen hanging around Nelson, Kearney, and Dolph. He is considered an outlaw or a "bad boy." Despite his reputation as a bully, it is significant that it is sometimes hinted that Jimbo is in fact Christian, with strong moral standards. At one point, when he revealed to Martin that the "paint" vendor that he got the unicorn tattoo from was actually a tattoo parlor at the Skewed Over event, he notably showed hesitance at beating up Martin at that point as he "had it rough already." even stating to the other bullies that it might not be a good idea to beat him up, although he ultimately decides to beat him up with the other bullies. He has been kicked out of all 4 Space Mutant movies.
Jimbo's parents are Mr. Jones and Carol Jones. It is constantly implied that his mother is sexually promiscuous, possibly working as a prostitute. She sometimes walks around topless, which impresses Kearney and Dolph. Jimbo has a sister; he, Nelson, Kearney, and Dolph use the case from her retainer as an ingredient in a stink bomb.
He is one of the best looking boys in town along with Dolph. Jimbo also had a skateboard, just like Bart. He smokes cigarettes filled with weed and drinks alcohol with Dolph. He may also use other drugs. It is also implied that Jimbo has a job as a police informant. Lisa saves Bart from the bullies, Jimbo says to Bart, "It's a lucky coincidence, you happen to be your sister's brother.". Another time, Jimbo laughs at Bart's pajamas, and mockingly asks if his mummy bought them for him. When Bart replies, "Of course, she did. Who else would have?", Jimbo looks blank for a while before saying that Bart has won (this time).
Jimbo enjoys intimidating his classmates and shoplifting (even with Kearney). His best friend is Dolph and hes also close friends with Kearney and Nelson. It is hinted that he comes from a well-off family, displayed when (with the school closed for a teacher's strike) he and his mother watch soap operas and sip tea together in a very nice living room. Given that Jimbo's father, Mr. Jones, seemed to be a beer-drinking lowlife when seen in another episode, it may be that Jimbo is an illegitimate child. His mother may be involved with "bad boys".
Jimbo is the leader of the gang of bullies at Springfield Elementary consisting of Him, Kearney, Dolph and Nelson. He is bossy and bratty. He has mixed feelings with Bart, most of the time he will think he is cool but sometimes he will bully or tease him.
 Love interest
Jimbo temporarily became the boyfriend of Bart's babysitter Laura Powers, on whom Bart had a crush. However, Bart got even one night when Laura was babysitting him and had Jimbo over. Bart made one of his trademark prank calls to Moe's Tavern, and told Moe when he found out that it was a prank that his name was Jimbo Jones of 1094 Evergreen Terrace (Note that the Simpsons' address was inconsistent in the early seasons). Moe came to the house with a rusty knife, and Jimbo started to cry pathetically. Laura broke up with Jimbo shortly afterwards. When Bart visited Darcy, Jimbo is seen holding a baby with strong resemblance to him. It's been implied that Lisa may have a crush on him. Jimbo is not a virgin.
Jimbo suggests that he stole dolls, because "they demean women". At one time, Homer tells Jimbo, "Your king commands it.", to which Jimbo boldly replies, "Jesus is our only king". Despite this, in support of Dolph's references to a long-haired carpenter, who "has a lot of crazy ideas about love and brotherhood", Jimbo adds, "His name's "Gunnar," and he's dating my mom. Sometimes, he buys us beer.". Then Bart said I thought Kearney was dating your mom
 Bongo ComicsAn issue of the Simpsons Comics revealed the backstory of Jimbo. When Jimbo was a new student at Springfield Elementary School, he wore a yellow short-sleeved suit, a pink tie, and blue jeans; in those days, there were no bullies, so nerds ran the school with a mix of high attendance, GPAs and cruelty. Jimbo's suit ripped off when the nerds pushed him on a chair with glue on it that ripped his suit off. Willie gave Jimbo the T-shirt that he now wears, and he was nicknamed "Jimbo" because of his low IQ. A water balloon snapped the hairband that held his hair in a ponytail, and Willie gave Jimbo the purple knit hat, that we now associate with him. Now, Jimbo looked like a bully, but he hadn't become a bully yet, then Bart told Jimbo that he should beat up the nerds.
 The Simpsons Game
 The Simpsons Hit & Run
 The Simpsons: Tapped Out
 Behind the Laughter
Jimbo is loosely based on the character John Bender from The Breakfast Club. Jimbo is named for the executive producer, James L. Brooks. He is voiced by Pamela Hayden (Tress MacNeille in The Telltale Head).
In The Simpsons comics, Jimbo comes to school as "James Jones."Although Jimbo is referred to as "Jimbo," that is not actually his real name. Although Nelson once referred to Jimbo as "James," Bart realized that Jimbo's real name is "Corky" in Season 7's "Bart the Fink" (though in Season 8's "Lisa's Date with Density," Nelson refers to Jimbo as "James" when he is defending Lisa, implying that "Corky" could be a nickname or a pseudonym). This may or may not be true. But in the end, it says that Jimbo's real name is "James." Jimbo's other known aliases are Jamesbo, Dr. J and Hector Guterriez (as revealed in Season 18's "24 Minutes", although this episode is considered non-canon).