Betony Burrito "Beth" Jakson IV (full title: Beth, the Pup Princess) is a character who exists in the future. She is a close friend of Shermy, who made her first and only appearance in the series finale "Come Along With Me."
She and Shermy appear to live in Marceline's now-abandoned house, a reference to how Finn and Jake lived in the Tree Fort, which originally belonged to Marceline. She is a descendant of Jake and Lady Rainicorn.
Beth is a large, round, yellow pup. As Jake's descendant, she shares his eyes, ears, and jowls, as well as a similar fur color. And like her ancestor Lady Rainicorn, Beth has a white horn on top of her head. She also has small ears and a large belly button, and she doesn't seem to have a nose.
In a failed attempt to capture the Prize Ball Guardian, Shermy found Finn's lost mechanical arm. To learn its origins, Beth suggests visiting the fabled "King of Ooo," who in their time is a lonely BMO. Now living in a house on the top of Mount Cragdor and surrounded by relics of his past, they're thought to be nothing but a legend. When Beth shows BMO the arm, they finally consent to tell her and Shermy about the Gum War, the battle against GOLB and the final fate of the people of Finn and Jake's era.
After their visit with the "King of Ooo," Shermy then remembers to have seen the Fern Tree (previously shown in "Lemonhope Part 2" and "Graybles 1000+") in his travels around Ooo. The two arrive at the tree and climb all the way to its top, finding the restored Finn Sword. She instructs Shermy to lift up the sword, leading him to mimic Finn's iconic pose seen in the show's opening sequence, as Beth assumes the pose made by Jake.
Beth has the ability to teleport objects from other locations through her belly button, as well as store objects inside of her belly button for transportation purposes.
- Beth, numbered as Pup #38,000, is a descendant of Jake and Lady Rainicorn.
- Her surname "Jakson" is based on the fact that the Pups are Jake's descendants.
- Her middle name, "Burrito," seems to have been inspired by Jake's love of burritos.
- Beth shares part of her name with Beth Tezuka, a character from Bravest Warriors, which is another series created by Pendleton Ward.