She assumed the surname Bannings during the imperial occupation of Crossbell.
When KeA is found by Lloyd Bannings and the Special Support Section during the Schwarze Auction on Mishelam, she appears to have lost her memory. Her outspoken character and innocence makes her loved by everyone and she herself easily befriends all of the SSS's associates.
It is later revealed that KeA is actually a homunculus cultivated as a reproduction of the Sept-Terrion of Mirage, Demiourgos, by the Crois family's lineage of alchemists. She was named KeA, derived from the idea that she would become the key to the origin of everything (all), "Key of A".
After creation, KeA has continuously slept for 500 years on the altar of the D∴G Cult. The Cult, not knowing KeA's true purpose, was led into believing KeA was the daughter of the true Goddess, as opposed to Aidios. Following the Crois family's commands, however, Arios MacLaine was tasked with removing KeA from the altar and hide her at the Schwarze Auction. It was by KeA's decision as the Sept-Terrion of Zero that she wanted to be protected by Lloyd.
Upon KeA's completion as the Sept-Terrion of Zero, she had not only inherited governance over mirage, but the two other higher elements - time and space - as well. This means that KeA possessed a terrifying power that allowed her to read and overwrite past, present and future alike. Mariabell Crois reveals that KeA had already used this ability during the SSS's fight against Joachim Guenter in which the team was originally killed as well as unconsciously causing every being she interacted with to love her including the members of the SSS. The latter reveal caused KeA to merge with the Azure Tree and become the Azure Demiourgos.
After the Special Support Section beat the Azure Demiourgos and released KeA from the spell, she began to follow the footsteps of the original Demiourgos by wishing herself out of existence. Lloyd, however, broke into KeA's inner world and persuaded her to return to her family at the SSS. This resulted in KeA losing her powers and becoming an ordinary girl.
|5||Critical Chance +100% (4 turns)|