Evadne

Japanese name:

エヴァドニ

Evadne is a Demon Sword of the Black Flame, who, like Aria, can take human form. In her human form, she is morose and taciturn. She was in Charlotte's possession but may have come from Siegfried. She transforms into a sword by chanting "Awaken, Cloak in Darkness, Finish thee and Slay God"

Voiced by: Satsuki Yukino (Japanese), Clarine Harp (English)

Wikipedia