Theodosia Electra

Theodosia Electra (テオドシア＝エレクトラ) is a Necessarius magician who uses Norse mythology as a base for her magic.

Volume SS2: The First Friday of February
Kanzaki Kaori tells the Jeans Store Owner that she got her information on the Jean Slasher's actions having the smell of Norse Mythology on them from Theodosia who investigated the incidents.