|“||Drop the butter knife, bitch!||”|
|— Jellybean to Penny[src]|
Jellybean is the younger sister of Jughead Jones and the daughter of Gladys and FP Jones. She is also a member of the Toledo Serpents. As well as a Junior mechanic, as she was shown working under a car in her mothers compound of old car parts.
Is wise beyond her years, and her favorite bands are Pink Floyd and Black Sabbath. Jellybean lives with her biker mom in Toledo where they run scams to make ends meet. And like mother like daughter: Jellybean — who goes by JB now — is quite the little con artist herself.
When Jellybean was younger, she and her family would spend a lot of time at the Twilight Drive-In, however, they often could not afford tickets for everyone, so the kids would hide in the trunk until they parked.
After Fred Andrews fired her father and he began drinking heavily, Jellybean and her mother went to live with Jellybean's grandparents in Toledo where she started to go by J.B. instead.
The Drive-In & Moving to Toledo
Jellybean was briefly seen in an old photograph of Jughead's when he was leaving the Twilight Drive-In, for the last time. According to Jughead, they would hide in the trunk of their parents' car until parking, as their family was often low on funds, and so sneaking into the drive-in was their only option. 
Jughead mentioned that he spoke with Jellybean over the phone. She wanted to be addressed as 'JB', instead of Jellybean because she thought it sounded cooler. He remarked that "she's ten years old, and listens to Pink Floyd on vinyl. I don't think she could get any cooler." Jughead also mentioned that she was helping their mother study for her GED. 
Jellybean appears in Archie's dream. She sits at the table alongside Jason, Cheryl, Pop, Penelope, Clifford, Reggie, Hiram, Hermione, Alice, Hal, Kevin, Tom, Sierra, FP, Toni, Jughead, Betty, and Mary in his dining room. Archie asks where his father is, to which Arti replies that Archie was supposed to go get him.
Jellybean is among the large crowd rushing to give Fred Andrews a welcome back home when Archie and Veronica bring his body back to town.
Dressed in his Stonewall Prep uniform, Jughead asks his father and sister how he looks. FP states that he looks like a gentleman, however, Jellybean appears sad to see him leave, even as Jughead promises her that he’ll be back every weekend. FP’s glad that Jughead will be attending. He’s somewhat a legacy. His grandpa Forsythe the First also went to Stonewall, though only for a couple of months until he dropped out. He quit at everything, including being a parent. He went out for a pack of smokes and never came back. FP didn’t mention this before because he wanted Jughead to make his own decision without any outside influences. It’s a chance for Jughead to do something good for himself.
Flash forward to Spring Break, Jughead is missing. Jellybean, Archie, Betty, Veronica, Kevin, Cheryl, and Toni join FP’s police-led search party for Jughead in the dark woods.
Jellybean, Betty, and FP help Jughead move into his room at Stonewall Prep. FP and Jellybean leave Jughead and Betty alone so they can say goodbye, suggesting the two of them go look for the vending machine to buy her some Triple Bubble. Once FP and JB are gone, Betty insists that she’s fine with Jughead attending Stonewall and they kiss.
Jellybean tells Betty how she upset with Jughead having left to attend Stonewall Prep. Betty can relate given that Polly’s away being deprogrammed at the Shady Grove facility.
Halloween night. As Jellybean carves out a pumpkin, she wonders why Betty isn’t in a costume. Betty replies that she’s dressed as Laurie Strode from the original Halloween film. The door bell rings. Betty answers to find two trick-or-treaters. One dressed as the Black Hood and another dressed as the Gargoyle King. She gives them candy and shuts the door. Jellybean asks when Jughead will arrive, but Betty isn’t sure. And so, Jellybean heads upstairs to play Minecraft. Betty rushes upstairs after hearing a thud from Jellybean’s room. She finds Jellybean laying on the ground bleeding. Jellybean jumps awake as it was merely a prank. The phone rings. Betty tells Jellybean to lock her room door and to not answer the phone.
While doing her homework, Jellybean is approached by Betty, who asks if she has any fake blood left over from Halloween, which she does. Later, Jellybean helps FP organize a search party for Jughead in the woods. Archie leads FP to Jughead’s body, lying down below in a shroud of bushes.
Betty, Alice, FP, and Jellybean sit around the breakfast table. The phone rings, and Betty’s answers. She starts to cry and falls into her mother’s arms.
Jellybean attends Jughead’s wake at the Jones house. FP welcomes everyone and thanks them for attending. He recalls how resilient, loyal, and loving Jughead was. Betty approaches the podium and reads a passage from one of Jughead’s favorite Sherlock Holmes short stories. Donna interrogates Jellybean, demanding that she admit that Jughead’s actually alive. Betty interrupts and still Donna claims this is all merely an act. As Betty kicks Donna out, she tells Bret to go for the coffin, however, Sweet Pea snatches him by his shirt and pushes him away. Betty then tells him, Donna, and Joan to leave.
Unlike everyone else, Jellybean discovered that Jughead was alive on her own. It was after Betty asked her for fake blood. Jellybean brought Betty the blood and asked if she needed it to help Jughead. She heard Betty whispering on the phone to Charles the night before. She didn’t ask to know where Jughead was, only that he was okay. Betty then revealed to Jellybean the entire truth behind Jughead’s disappearance.
At the Jones-Cooper house, Betty, Jughead, Charles, Jellybean, FP, and Alice watch her news report. Betty congratulates her on a job well done. Alice thanks FP with a kiss for providing her with the inside scoop. Betty then leaves, explaining that she has one last T to cross.
As a child, she was slim and short with medium-length black hair and brown eyes. Now, as a preteen, her hair is light brown, but her build is still slim and short as she hasn't reached her adult height.
She is an assertive individual and has a no-nonsense attitude due to her tough upbringing. Unlike her brother, Jughead, she is not as close to her father and resents him for being distant after the separation of her parents. It is known that she likes Pink Floyd and movie theaters, much like her older brother. She also appears to be a very obedient child as shown when she informed her mother she did exactly as she told her to do with her father, stating that she had succeeded in having FP wrapped around her fingers.
|“||By the way, Jellybean wants to go with JB now. She thinks it sounds cooler.She's 10 years old and listens to Pink Floyd on vinyl, I don't think she could get any cooler.||”|
|— Jughead about Jellybean[src]|
Jellybean's relationship with her brother, Jughead remains vague given that she and Jughead were separated by their mother's move to Toledo to stay with their grandparents. She went with their mother while Jughead stayed behind with their father. Jellybean seems to be very close to her brother, even mocking his arrival to her mother's garage albeit demanding another Serpent to let him through the gates with Archie. Jughead also thinks very highly of his sister and mentions her several times, such as when he told Sierra McCoy about their family's trips to the Twilight Drive-In.
When Jughead reunites with Jellybean, she also meets Archie. They appear to be friendly towards each other. Later that night, when Archie mentions that he used to date Hiram's daughter, Jellybean takes this to mean that Archie is now single, exposing the obvious fact that she has a crush on Archie. Later, when Archie is attacked by Penny Peabody, Jellybean saves him by shooting Penny in the head with her slingshot.
- "Chapter Fifty-Eight: In Memoriam"
- "Chapter Fifty-Nine: Fast Times at Riverdale High"
- "Chapter Sixty: Dog Day Afternoon"
- "Chapter Sixty-One: Halloween"
- "Chapter Seventy-One: How to Get Away with Murder"
- "Chapter Seventy-Two: To Die For"
- "Chapter Seventy-Three: The Locked Room"
- She listens to Pink Floyd on vinyl.
- She prefers to be called "JB", a possible reference to JB Moranville, a Riverdale producer who unfortunately passed away in October 2016.
- In the Archie Comics, her real name is Forsythia Jones, a mirror to Jughead's real name Forsythe.