Third Person POV
"It all started 4 decades ago. The first case ever to be seen that was similar to these in our present time, and when we first meet you." Skylar stated.
4 decades ago
"Bill Wait!" Skylar exclaimed as she tried to catch up to Bill.
"Come on Sky or we will be late!"
"Can't you just teleport us there?" She asked as she had fallen into step beside him.
"You know i cant Skylar not after we almost died last time." Bill said as his bangs covered his face.
"Im sorry Bi-whos that?!" Skylar shouted running over to the person.
Bill ran after Skylar and held the brunettes head in his lap while his younger sister checked for any wounds.
The male brunnette groaned and opened his eyes only to see a young blonde male and a young female with half orange and half pink hair.
'Who are these people?' The brunnette thought.
"My name is Bill Cipher and this is my little sister Skylar." Bill said.
"I'm Mason but the elders call me Dipper." Mason says as he gets up.
After this encounter they spend many days together hanging around and having a good time, Mason met Kill and Will, but something sinister was happening while the 5 were having fun...someone was plotting to burn down Mason's village.
"Sir...it's ready." A mysterious figure said.
"Excellent," the second mysterious figure said with a dark and evil chuckle, " we leave at dusk."

Okay I think I'll leave it I want to write more of it but I can't put it into words 😅
Anyways only one person responded to my q and a chapter so this is for  ReginaldKastle24

Mabel: no! We are not a thing, I don't even like her like that!
Me,Bill,Dipper,Skylar,Kill,Will, and Stan: Pacifica deserves so much better then you if your that blind.
Mabel: *scoffs and walk away*
Me: *neutral face* anyways  hope you liked the answer and I hope you guys enjoyed the flashback, the next chapter will be like this as well and this is the last chapter I'm doing for their backstory. Bye bye 😊