Weirdmageddon: Dream Demon takeover (Billdip)
Dipper and Mabel are now 19 but when they were 13 and dipper was offered to stay in gravity Falls, he took it. He stayed and Mabel left.
But now she was coming back she wanted to spend the last summer they had of being teens together. They set it up so that them and all of their old friends would come back to gravity Falls and spend the summer together again. But with all of the zodiacs back in the same town, on a sunny day, an uninvited guess may be joining them.
You know the drill, I don't own any of gravity Falls, it's not mine, the music isn't mine either.
All Character (other than Ana and OC that come in later) and all Gravity Falls settings belong to Alex Hirsch, creator of Gravity Falls