#the idea is that if Ford is blind he can't see whether someone is possessed by bill + bill would make a helluva fiddleford impression

[hua-liansimp]

Gravity Falls canon divergence AU where Bill does send someone to steal Ford's eyes and then possesses Fiddleford to approach blind Ford. Fiddleford/Bill nurses Ford back to health, and then pretends to be sorry for leaving Ford, he sticks around to help him adjust to losing his sight. Eventually, an extremely exhausted and broken Ford breaks down and confesses everything that truly happened during their partnership, and Fiddleford/Bill "comforts" him. He promises to never leave him, saying that he won't let that "monster" hurt Ford ever again.

Bill thinks it would be too risky to convince Ford to continue with the portal so soon, afraid of arousing his suspicion, so he just ends up moving in and caring for blind Ford, gaining his trust everyday a little more. What Bill doesn't expect is that he enjoys their current situation way more than he thought he would (Ford is dependent on him once again, he doesn't even know he's being tricked, the fool, but also Bill can be close to him again, they can play and banter and it's like nothing ever changed), and years pass without any work being done on the portal as they grow closer and closer.

It's only decades later that Bill slips up and leaves for some business in the middle of the night. Ford wakes up for a cup of water to find mind broken Fiddleford wandering around his kitchen muttering about a demon living in his head and keeping him trapped.