so basically bill lost his power and was human and he basically begged you to let you stay with him and the rest of the gang and blah blah blah so Dipper accidentally spawned zombies again and you all were fighting them until Mabel saw one zombie with a Britney Spears shirt she paused Dipper and you look at her while bill was beside with a bat
Dipper:"Mabel what are you doing.." She looks at the zombie and began to sing Mabel: "Oh, baby, baby Oh, baby, baby Oh, baby, baby How was I supposed to know" Dipper:"Mabel stop it.." Bill perks up and joins her Bill and Mabel:"That something wasn't right here Oh, baby, baby I shouldn't have let you go And now you're out of sight, yeah" Dipper facepalms and sighs while you started to get hyped Bill and Mabel:" Show me how you want it to be Tell me, baby 'Cause I need to know now, oh, because" You soon rush in while a smile You, Bill and Mable:" My loneliness Is killing me and I I must confess I still believe, still believe When I'm not with you I lose my mind Give me a sign Hit me, baby, one more time" Just then bill grabs the bat and hit the zombie in his head while Mabel then looks a bit traumatized Bill:"Well that was fun aren't I right shooting star and sunlight?" He usually called you guys my your sign which in this case you're sunlight