My Demon "Sister"

Skye found injured Immortal Lord Caelan her husband. Caelan recovered, then abandoned her. Skye stumbled into the Demon Realm, mistook Demon Lord Malachi for a fairy, calling him "sister." Malachi was disarmed by her. When Caelan returned, Skye learned her Essence of Wisdom was taken to mend Divine Lord Caelan's soul. Malachi retrieved the Essence of Wisdom for her. Skye became intelligent, but Malachi was sealed. She walked into the seal to join him.