Dipmay_gravityfalls
Set 23 years in the future of Gravity Falls...
When a young couple is being hunted by a strange organization, they seek the Mystery Shack for safety. Welcomed by an adult Mabel Pines and an elderly Great Uncle Stanford, Jake and Dee discover the hidden past of the Pines family, while under an assault from a secret society trying to kill them.
Rated T just to be safe. Some bad language and later sexual themes.