Sasha



Sasha was one of Brimir's familiars she made a pact with Brimir to allow him to experiment on her but made he her his familiar, something Sasha was not pleased about. In his defence, Brimir meant no harm to come to Sasha when he made her his familiar.

Sasha killed Brimir as she stabbed Derflinger into his heart while he tried to kill off the elves for reasons not yet revealed as of the 19th Light Novel.

Trivia
Despite already being Gandalfr Sasha is also The Heart of God as well.