Rossweisse

Rossweisse (ロスヴァイセ) is Odin's bodyguard and the one who always stops him when doing ecchi things. Odin always teases her for being a Valkyrie that has no boyfriend. After the battle with Loki and Fenrir, Odin dumped her in Ise's town. She then gets persuaded by Rias to become her servant. She remains in Kuou Gakuen as a teacher. She is still figuring out if she likes Issei. She moves in with him. Rossweisse is extremely bitter on the fact she doesn't have a boyfriend and gets angry to the point of going berserk when made fun because of that.