The vorlikai demon is an advanced nabassu demon. Nabassu are formed from the souls of evil gluttons, especially cannibals and those who eat undead flesh. Unusually for a demon, it is birthed on the Material Plane rather than the Abyss. It lives a solitary life, and its goal is to transform as many living humanoids into ghouls as it can. It gains in power for each ghoul it creates, and when it has created enough ghouls (the number required varies for each individual, but is never more than 20) it grows in size and is transported back to the Abyss. There they continue to grow, ultimately becoming fearsome vrolikai demons.
This black-skinned, bat-winged demon has four arms; a long, thin tail; and a leering, fanged face with dead, white eyes. A vrolikai is 14 feet tall but weighs only 500 pounds. Unlike other demons, it does not form from a sinful soul—it instead manifests from a nabassu demon that returns to the Abyss after growing to maturity on the Material Plane. Not all nabasus survive this transformation, but those who do become powerful indeed—vrolikai usually rule large regions of unclaimed Abyssal land, and often serve as assassins or ambassadors to demon lords in need of an agent in a distant realm.