One of the Million Favored Ones.
The Million Favored Ones are a mysterious group of a 1,000,000 human-like beings that are said to be the spawn of one of the Outer Gods known only as Nyarlathotep.
They, like the many Nyarlathotep-based cults (both human and inhuman), worshipped Nyarlathotep and they kill in his name.
The Four Horsemen of Nyarlathotep are said to be part of this strange society of monstrous fanatics.