Billdip (Assassin AU)
Dipper and Mabel haven't had what you would call a normal childhood. Instead of playing at the playground, they fought and learned how to use a No. 7 M21 sniper at the age of ten. Born and raised cold blooded assassins. By seventeen they were practically pros, no job was too hard for the Pines twins. But when a mission of their's has to end the life of Bill Cipher, teen idol, and of course son of the all dominating CEO Carswell Cipher, things get a bit tricky. A job like this was sure to be a success, but little did they know that their whole lives were going to change.