Elisabeth Weil Sonntag

Elisabeth Weil Sonntag, also known as Ellie, is a former demon princess, as well as the last surviving member of the Sonntag Republic's deposed royal family. She is Wendelin von Benno Baumeister first Demon wife

Background
She became part of Wendelin's growing harem of wives and mistresses at an unspecified point during the long time-skip prior to the events in Ep. 163 of the Web Novel.

Wendelin von Benno Baumeister
Her Husband

Trivia

 * Wendelin's eponymous descendant named her as one of the official Baumeister wives - as well as his direct ancestor - in Ep. 163 of the WN, thus confirming that the contemporary von Benno Baumeister margrave bloodline possesses royal (Helmut Kingdom and Akitsushima), imperial (Duke Philip and Duke Mizuho households) and demon (Sonntag) heritage, strengthened through intermarriage between the various branch families over many decades.