Weak to Black knight weapons ( Greataxe, Sword, Greatsword, Glaive) and Dark Damage.Attacks deals Standard Damage and Fire Damage.Can be fooled with alluring skull, and be charmed with rapport.Other: Fire Gem (Undead Settlement), Soul of a Demon (Catacombs of Carthus).Catacombs of Carthus: after you break the hanging wooden bridge, go down using it as a ladder to find the demon near a mimic and amongst many skeletons.Undead Settlement: find the tower lift of the right of the area and drop down mid-way onto some rooftops, then further down to meet the demon.

It is found roaming the Undead Settlement and Catacombs of Carthus. Demon is a mini-boss enemy in Dark Souls 3.