Mabel Pines is the older twin sister of Dipper Pines. She is optomistic, friendly and a little silly. Mabel as well as Dipper are spending their summer at their Great Uncle Stan's tourist attraction, The Mystery Shack in Gravity Falls. The two twins discover many secrets.
- In Gravity Bound one of her Don't Care names is "Ariel" referencing the twin sister of Gravity Falls creator Alex Heirsh.