Quelana of Izalith is the mother of pyromancy and a magic trainer of pyromancy in Dark Souls. She is found in the poisonous swamp of Blighttown, directly across from the entrance to Quelaag's Domain after ringing both Bells of Awakening.
When the Witch of Izalith tried to recreate the First Flame and failed she created the Bed of Chaos, from which all demons were born. Unlike her sisters and brother, Quelana escaped unharmed and wandered Lordran in guilt. Wishing to free herself, Quelana seeks the death of her corrupted sisters and the abomination that her mother created.