Marianne de Tristain

Marianne de Tristain (マリアンヌ・ド・トリステイン, Mariannu do Torisutein), also known by her title Archduchess Marianne (マリアンヌの大公, Mariannu no Taikō), is a former Queen of Tristain. She is the queen consort of Henri de Tristain during his reign and succeeded him as queen regnant after his death; their only daughter is Henrietta de Tristain.

Background
Marianne is the only daughter of Philippe III de Tristain. When she was 13 years old, Karin de Maillart was assigned to be her personal guard. As a princess, Marianne would often sneak out of the castle, bringing Karin and Sandorion de la Vallière with her.