This is an alternate universe of gravity falls so like dippers is named Mason dipper pines and Mabel is obsessed with giddion however he doesn’t like her and Will cipher is Bill ciphers brother so like how most ship dipper and bill in reverse falls will and mason are shipped however Mabel and mason see will as a slave and treats him badly but sometimes mason is sweet to will but other than those things and the fact that mason and Mabel are older it’s all just like gravity falls but reversed and how this came to be well mason had all three of mystery books and he learned about 4 Evil demon siblings willow (will), bill, kill, and Rage however will fully named willow cipher was the only female, the most powerful, and the eldest sibling the second strongest seems to be the cast away which is rage anyways Mason decided to summon Will and that’s how it came to be now mason opened a portal to the original Gravity falls universe shoving him, will, and Mabel inside.