Grethe Wenzel (グレーテ・ヴェンツェル, Gurēte Ventseru?) is the developer of the XM2 Reginleif and the heir to WHM, a family owned military-industrial complex. She was a pilot of the Federacy's Air Force, but as the Legion has rendered aircraft unusable, the Air Force was disbanded. She is the commander of the 1028th Trial Unit, created in order to test her newly developed Feldreß.
Grethe has blond hair and purple eyes. She cuts her hair short and wears the Federacy's military uniform consisting of a black suit and red tie covered by a dark steel-colored panzer jacket.