Pickman

Pickman is a serial-killer killer living in Pickman Gallery in the Commonwealth.

Background
Pickman is a man with a strong dislike for raiders, killing anyone that wanders into his home. While generally presenting himself as collected and polite, he's extremely disturbed; casually mentioning his hobby of collecting the raiders' heads. Along with this, he considers himself to be a brilliant artist, painting with the blood of those he kills and creating horrific sculptures of body parts. The Sole Survivor first meets Pickman deep within the tunnels of Pickman Gallery while he is being attacked by Slab, a raider who wants to take revenge on Pickman for killing his men.

Other interactions
If the Sole Survivor kills Slab and the two raiders on either side of Pickman and then speaks to him after, they are rewarded with Pickman's key, which opens a safe on the ground floor of the Gallery, containing Pickman's Blade and Pickman's thank you note. If the Sole Survivor opts to let the raiders kill Pickman or to kill him themselves, his corpse can still be looted, but the note will not be in the safe.

Appearances
Pickman appears only in Fallout 4.

Behind the scenes
Pickman is named after and based on the uncanny artist Richard Upton Pickman from the short story Pickman's Model by H. P. Lovecraft.
 * This character also makes an appearance in Lovecraft's story "The Dream-Quest of Unknown Kadath", and it may be interesting to note that this Pickman is described as having become a ghoul (though the description has little in common with the Fallout variety).