It's your friend, Bill, here to tell you that this is an Alternate Universe. The person, classified as Brad doesn't actually exist in Gravity Falls, and The author, DOESN'T OWN GRAVITY FALLS. Warning advised. Enjoy the story. Reality is an illusion. The Universe is a hologram. Buy Gold!
Dipper and Mabel had just defeated the gnomes, and stopped them from marrying Mabel. Dipper had fallen asleep a little after Mabel had shot their light through a window using her grappling hook. Suddenly, something woke him. He sat up in surprise. Dipper thought he heard a voice. He looked around the attic in alarm. Mabel was fast asleep. Nothing seemed to be amiss, except for the fact that their window was open. Dipper got up, and looked through it. There was a bright light in the middle of the forest. He flipped through the journal as for a clue as to what was the light coming from. Nothing. He put on his shoes and his jacket, plus the pine hat. He climbed up on the windowsill, and jumped down. He rolled on the grass as he landed, slightly winded. Dipper looked at the light, it was close. He slowly edged toward the forest, weary of the creatures of the nighttime.
Dipper ran up to a tree, the light shining brightly by it. "What is that?" He whispered, wondering what was the light coming from. Dipper edged towards the opening in the trees. He peeked his head around the tree and saw... a shrine. Dipper stepped into sight. The light was coming from a boy, about his age, 12. He looked somewhat like Dipper. The shrine was a simple wall of stone with a little bed of stone in front of it. The boy didn't move. Dipper looked at the stone wall. It was a drawing. It depicted a little triangle man with one eye, brightly yellow, and a brick pattern. It had a top hat, and a little black bowtie. There was a circle around it, its arms and legs outstretched towards the circle. Dipper swore he saw that in the journal before. He took it out and flipped through it, until he found the page with the same triangle man. "Bill Cipher... Can't be trusted... Dream Demon?" Dipper said to himself, reading the passage of Bill. He closed the journal and studied the symbols around the circle. It's a zodiac, not a circle. Dipper realized. It had many symbols, but a few caught his attention. The pine tree, for instance. The symbol on Grunkle Stan's fez. "Two odd things in the same 24 hours? This might have to do with this, Bill fellow." Dipper commented. Suddenly, as Dipper drew near to the Shrine, the Pine tree symbol on the zodiac started to glow, extremely bright. There was a flash of light, and Dipper covered his eyes. When he felt the light recede, he looked back. The shrine was gone. The boy was still there. Dipper then studied the boy. He wore a black Tee with green flannel, and had blue jeans, his shoes were black, and his hair acted the same as Dipper's. Dipper noticed something. There was a strange shape on the boy's forehead. Dipper crouched, and moved the hair in the way. It was a birthmark. But it was in the shape of a dragon. Right where Dipper's birthmark was on his forehead.
Dipper shook the boy. After a while, the boy's eyes opened, and rolled backwards from Dipper. He looked extremely on edge.
Author's note: This was an extremely short chapter. I usually go for 1,000 words, but I wanted to get this out sooner. Anyways, welcome to the first chapter of my Gravity Falls fanfic. As Bill said, This is an AU, and the story will change. A LOT. Thank you for reading, and review any errors, or comments. Thanks for reading!