Maria Graceburt serves as a senior instructor and administrator at Garderobe Academy under Headmistress Una Shamrock during *My-Otome 0~S.ifr~*. A rigid adherent to the academy’s founding doctrine of peaceful diplomacy, she opposes Una’s tactical deployment of the Five Columns against Schwartz, advocating instead for conflict resolution without military intervention. Her convictions stem from prior experience as a Coral-class student and the loss of her sister Monica, an Otome killed in the War of the Dragon Lord. This tragedy fuels her disillusionment with the Otome system’s sacrificial demands, prompting her to expel students unprepared for its harsh realities.

During Windbloom’s Artai invasion, Maria retains her teaching position but openly criticizes the new regime, dismissing figures like Nina Wáng as unqualified for Meister status due to their inexperience. Her combat capabilities include a Robe activation that temporarily restores her youth, enhancing her speed and agility—a transformation demonstrated during the Fuuka Castle assault that contrasts sharply with her austere reputation. In *My-Otome Zwei*, she is petrified by the entity Yuna while investigating the Fumi System chamber but is later restored alongside other victims.

As Una Shamrock’s aide and Pearl Class homeroom teacher in the prequel, Maria assumes the headmistress role after the Five Columns’ defeat, revoking all Columns’ Otome licenses except Elliot Chandler’s as disciplinary action. Promotional materials mirror her Robe’s youthful visage from the main series. The manga adaptation reduces her role to brief appearances focused on stern critiques of student conduct, maintaining her consistent prioritization of tradition, institutional integrity, and pragmatic governance across all media.