Book 3: Bill's return: Wanting his favorite...
☾ ★ Book Three ☾ ★ : After Bill wanders around in Dipper's mindscape toying around with him, making him think he had lived a life with him, Dipper foolishly agrees to any deal Bill asks, thinking he's a good guy now because he formed a bond with him in many ways. After Dipper wakes up, he realizes he's made a huge mistake. He then tells Ford that Bill had visited him in his dream. Ford scrambles to figure out how to finish the weapon he works on after he "erased" Bill, actually revealing that Bill could never be fully eliminated but he can for long periods of time. After a short while, Bill comes back to the shack seeking his revenge but also to pick up a package which is now rightfully his and is very excited to open it up and try out~
Please read the previous book if you haven't read this one! It will make more sense. Trust me!
Disclaimer: Gravity Falls does not belong to me. The creator of the show is Alex Hirsh and the show Gravity Falls is owned by Disney XD. This is a fan-made story between the character Bill Cipher and Dipper Pines.