Desolation Denied

From the introduction:

Krysophax is a fallen angel. Once one of the prime movers in Pelor's armies she was seduced by a cornugon and fell for him completely - such is the mystery of love. Expelled from Pelor's realm, and discarded by the Cornugon, Krysophax fled to Sigil to establish herself in her own right, free from constraints and responsibilities and no longer beholden to any other power. Now the Cage is a funny place, and it changes folk - after a few centuries in Sigil Krysophax no longer thought or acted like the being of purity and good that she was created as, but had instead begun to become more and more like the mortals around her. Indeed so like them did she become that she began to believe that, perhaps, she might become one.