Medusa

A powerful tower witch who was imprisoned at Rothenberg in a monolith but was able to escape. She is the eldest of the gorgon witches. Though a powerful witch, her eyes and arms were sealed, thus keeping her from using her powers at its full potential and is limited to only using "pseudo-petrification." She nearly defeated Kagari and almost captured Honoka; however, Evermillion appeared and was able to thwart it after Honoka swallows the medicine given to him by Chronoire which breaks the seal that has kept her in Honoka's body.

(Source: Anilinkz)