When you're a machine and your only purpose is to kill all humans.What do you do once they're all gone?

a scifi cross fantasy

A Gravity Falls fan story Gravity Falls is property of Alex Hirsh and the other amazing people who worked on it for 2 beautiful seasons. Gravity falls also belongs to Disney channel. This is a fan story and has nothing canon to do with Gravity Falls. Now all thats out of the way please enjoy Bill Cipher a fan story.