Keyhole

 is a demon and an interdimensional criminal, from an unknown dimension, that appears during the events of Weirdmageddon.

Background
Eons before the events of the series Keyhole indulged in criminal activities before being called together by Bill Cipher, along with 8 Ball, Amorphous Shape, Hectorgon, Kryptos, Teeth, Pacifier, Pyronica, and Xanthar.

Season 2
In "Weirdmageddon Part 1," during the cold open, Bill introduces Keyhole with the rest of his demon friends to the residents of Gravity Falls. Afterwards, on Main Street, Keyhole and the other demons watch Bill turn Ford into a golden statue and taunt Dipper before burning the journals. Later in the episode, Keyhole is seen drinking Time punch with Pacifier and enjoying the "V.I.P." party Bill is having at the Fearamid until Time Baby and the Time Police crash the party, but to the demons delight Bill vaporizes Time Baby and his squadron. The party then continues as Keyhole and the other demons rejoice over Time Baby's presumed death.

In "Weirdmageddon 2: Escape From Reality," Keyhole and the rest of Bill's minions attempt to leave Gravity Falls and spread their chaos across the world, but are stopped by an invisible barrier around the town.

In "Weirdmageddon 3: Take Back The Falls", he participated in the battle against the Shacktron. Following Bill's defeat, he was sucked back to the nightmare realm along with his fellow nightmares.

Appearance
Keyhole has a blue humanoid body with a forehead that resembles a keyhole. Keyhole has a darker shade of blue around its eyes, a pink nose and small blue aura.

Trivia

 * In concept, Keyhole was to have green skin.

Keyhole Замочник