The Second Anguis of Ouroboros, also known as the Azure Abyss. She is originally a witch from the Hexen Clan.
During the civil war, she pretended to assist the Noble Alliance, but was simply using them to set the stage for a battle between Rean and Crow's Divine Knights for the Phantasmal Blaze Plan.
However, due to Duke Cayenne's selfish interruption, she was unable to prevent the awakening of the Vermillion Apocalypse. As a result, she lost Crow and the Phantasmal Blaze Plan was stolen from her by Osborne.
Leaving Crow's body with Class VII, she teleported away and shortly thereafter, cut off all communication with Ouroboros. She's currently on the run from the society, the Intelligence Division, and the RMP as she tries to uncover the truth behind Osborne and the mysterious Black Workshop.