Bill's POV: So, it's official, she agreed, and I'm nervous. What if I say the wrong things? UUUUUGH TOO MUCH TO WORRY ABOUT!!!
We walked home together in silence. It was a bit too awkward for me, but before I could strike up a conversation, we had already made it to Molly's doorstep. "Sooooo tired.." Moll slurred, yawning. "I'm gonna go upstairs to bed, 'kay?" "Yeah..I think I'll do that too.." I replied with the same enthusiasm as she was using. We both yawned as we went up the stairs.
Molly walked into her room and I walked into mine. "G'night Moll.." "G'night Bill.."
As soon as I knew she was asleep, I went into action. I turned into my demon form and slowly floated into her room. Making sure not to disturb her, I shrunk to the size of a puppy, snuggled up next to her, and fell asleep.

Molly's POV:
I woke up to the sound of birds chirping. Apon opening my eyes, I saw a tiny, yellow, glowing triangle snuggled up against me. I smiled and giggled quietly, trying not to wake him.
After a couple seconds, I decided it was time to wake the demon. "Billy, wakey wakey!" I whispered. "Mmmhh, ten more millennia..." "Get up," I chuckled, "I know you're awake!"
After a couple more seconds, Bill reluctantly opened his eye. He got up and went to his room, giving me privacy to get ready for the morning. As I finished getting dressed, I smiled. I had gotten something for Bill and I know he'll like it. But first, we were going to go to the Mystery Shack and hang out with the pines.
I got downstairs, made breakfast, ate, and waited for Bill. "Bill, you aren't back in bed are you?!" ".....No.." "You hesitated." "No I didn't..." "Get up Fuzzy Dorito!" After a bit of waiting, Bill finally made it down the stairs. Before we left, I left a note for Bill, next to a gift box.
We made it to the Shack and I knocked on the door. Instead of Dipper or Mabel though, Stanley opened the door. The twins were behind him, looking around him at me and Bill. "Hi..." Bill greeted awkwardly. "STANFORD!!" Stanley yelled, then slammed the door in our face. "Well, I guess we aren't hanging out to-" The door swung open, revealing Stanley and another man who looked almost exactly like him but with six fingers, being held back by two screaming Mystery Twins.
I looked at the sight in confusion, then at Bill, who looked as though he'd just seen a guy with three heads. "Bill," Stanford rolled up his sleeves, "stay away from my family and their friends!" His hand sparked and Bill was blasted against a tree.
I gasped as Bill slowly got up. "I'm-I'm not h-here to hurt anybody.." He said, wincing from the blast. "He's telling the truth! Listen to h-!" "Go back inside kids.." "But-" "GO BACK INSIDE!" Stanford said, making the twins run back inside.
"Why are you here, Bill?!" "I just-" "WHY ARE YOU HERE!?" He screamed. "Listen, I-I don't want a fight.." "Well too bad! I'm gonna kill you once and for all you two dimensional monster!!!" He said as he started to float, his arms sparking and lighting up, and an amulet, formerly covered by his shirt, glowing and floating off of his chest. "Take the amulet off and settle do-!" The demon was interrupted as he was, yet again, blasted into a tree.
I could tell, just by looking at it, the amulet wasn't the one Gideon used. It was red and circular, with a black cross in the center. I knew....

It was for killing demons.

Bill floated upward, his hands starting to catch on fire. "Fine, you want a fight? I'll give you a fight!" He said as he chucked a few fireballs at Stanford, who just quickly dodged them. Beams of light were shot at the demon, who blocked and continuously threw balls of fire at his opponent, occasionally blasting beams of his own at the man.
"STOP IT! GUYS! WHY DO YOU HAVE TO FIGHT? CANT YOU JUST-!" But I couldn't finish my sentence, as I was thrown backwards by one of the beams in the crossfire, felt my head smack into the hard bark of a pine, and felt myself...

slip away..