|Aliases||The Philosopher's Catalyst|
|Family||Wilhelm Eiselstein (father)|
Selene used to help her father with his alchemic experiments as he tried to obtain the legendary amplifier: the Philosopher's Catalyst. However, she got caught in a rebound from one of his attempts to create a prototype of the Catalyst, and her body mutated. As a result, the Catalyst, taking the form of a glowing white wing, fused with her and she became the girl Wilhelm now calls Armony. Armony however, having memories of playing with Selene as a child, has no knowledge of the fact that she (in a sense) is Selene, and believes that Selene was her older sister who had died. There is a grave for Selene at the church near Hiessgart that Armony often visits and leaves behind an Etherflower for her, but Armony does not know that the grave holds no body of her "sister".