Will might find a way to escape on his own. Since he is also a Cipher, he could have some hidden powers or tricks up his sleeve. Maybe he manages to outwit Bill and gets away, which then sets up a cat - and - mouse chase between them throughout the fanfiction world. The story could also take a darker turn. Bill might start to torture or manipulate Will, changing Will's personality or making him do things against his will. This could lead to a conflicted Will, and the other characters might have to deal with this new, changed Will when they finally find him.
If Bill Cipher kidnaps Fanfiction, it could lead to chaos in the fictional worlds related to the fanfiction. Bill Cipher is known for his chaotic and unpredictable nature. He might manipulate the stories within the fanfiction, change the characters' fates in wild ways, or use the fanfiction as a tool to gain more power in the multiverse of fictional realms.
I'm not entirely sure specifically what that fanfiction is about. It could potentially be about Bill Cipher achieving or obtaining Will Cipher in some way, perhaps in a strange or otherworldly scenario within the context of the Gravity Falls universe. It might involve some sort of power play or a very unique plot device that only fans who have read it would know for sure.
One possible plot could be that Bill takes Mabel to his dimension. There, Mabel has to use her wits and creativity to outsmart Bill. Maybe she befriends some of the strange creatures in Bill's realm who help her in her escape plan.
Well, in some fanfictions, Bill might kidnap Will to gain more power. Maybe Will has some special ability or knowledge that Bill wants to use for his own evil plans.
One great Bill Cipher fanfiction is 'The Cipher's Game'. It has an interesting plot where Bill interacts with the main character in a dream - like world filled with strange and mind - bending challenges. The author does a wonderful job of capturing Bill's chaotic and mischievous nature.
One aspect of Bill Cipher and Dipper fanfiction is the exploration of their complex relationship. Bill is often depicted as a menacing and powerful entity, while Dipper is curious yet cautious. In many fanfictions, Dipper might be lured into Bill's schemes, creating a lot of tension and drama. It's a great way to expand on the personalities and potential interactions that were only hinted at in the original show.
I think Kakashi would also be a great character to pair with Bill Cipher. Kakashi is very intelligent and experienced. His encounter with Bill Cipher would be full of mind - games as he tries to figure out Bill's motives and powers while also protecting the village from Bill's chaos.
Dipper Pines could be one of the main characters. He might be the one who first discovers Bill's transformation and tries to figure out if it's a trick or if Bill is truly changing. His inquisitive nature would make him a great foil to Bill's new human self.