From one of the upper levels of the Nine Hells. She didn't dislike those on the Material Plane like other fiends. She was promised to another Incubus named Hekim as a consort and did not like him. So she managed to escape and stumbled across Arden Greyspire.
The two of them killed Heckim, sending him back to the Nine Hells, but did not purify his body, allowing him to return.
Wife of Arden Greyspire, and granted a boon by the Fey to be a fey succbus instead of a fiend.