Soul of Bed of Chaos | Dark Souls Wiki

Soul of the Bed of Chaos and the mother of all demons. This Lord Soul was found at the dawn of the Age of Fire.
The Witch of Izalith attempted to duplicate the First Flame from a soul, but instead created a distorted being of chaos and fire. Its power formed a bed of life which would become the source for all demons, and is more than enough to satiate the Lordvessel