Long ago, she was in love with a young bard (some fans speculate it to be King Arthur), but the Judgement Gate caused them to be separated forever.
Eventually, she finds Celestine in the Lunar Dungeon. She breaks the locks without too much effort, and allows her body to serve as a vessel for Celestine to use.
She also has a human disguise, and used that as she acted like an incoming freshman to the Nekomi Institute of Technology, and joined the Auto Club.
Because Celestine told her it would be advantageous to their plan, Morgan tried her best to get between Keiichi and the amnesia-stricken Belldandy. However, feelings within her began to well up, and due to a number of reasons, (detailed below) she began to fall in love with Keiichi. If Celestine was to have Belldandy, then Morgan may as well have the leftovers.
Morgan's own reason for joining Celestine in changing how the world was built could be attributed to the fact that she is a very lonely person. She had defied her family, her heritage in falling in love with the young bard, and the Judgement Gate's curse had separated her from her lover forever.
Being separated from her lover, nobody else would probably approach her, due to the fact that she is still heartbroken, and that she was a faerie. The social stigma of being near anybody of another race would be enough to cause her loneliness. Also, her attraction to Keiichi may have fuelled her on, as she was reminded of her own failed relationship.
All in all, Morgan gets one of the best tracks on the movie OST (Morgan ~ amor ~ tristis) (translation: Morgan ~ love ~ sadness), and she also gets some very cool fight scenes.
Eventually, at the end of the movie, she realizes that her and her lover were separated because she herself doubted the relationship, and stayed behind at the Judgement Gate to tell others that there was hope to pass through the Gate with the blessing of the gods, if they truly believed and trusted in each other.
- Morgan le Fay is named the sorceress and half-sister of King Arthur. Some sources say that le Fay was often compared to the goddess Modron, a figure derived from the continental Dea Matrona featured with some frequency in medieval Welsh literature. "le Fay", from the French la fée, means 'fairy'.