Medhi, whose real name is Airi, is a teenage girl with blue shoulder-length hair, matching eyes, and a pale complexion, noted for her prominent bust. She typically wears a white dress paired with a matching corset, stockings, and boots. Initially presented as a kind and obedient honor student, she dutifully follows her mother Medhimama's demands for academic excellence and a perfect public image. This compliance masks deep-seated resentment toward her overbearing mother, whose narcissistic drive to be recognized as the "number one mom" involves constant pressure and public bragging about Medhi's achievements. Medhi privately vents her frustration through physical outbursts like kicking walls or rocks when alone.

Her breaking point comes during a school festival when Medhimama forbids friendships to maintain superiority. Realizing her mother's actions stem from pure ego rather than genuine care, Medhi unleashes suppressed rage, transforming into a powerful dragon. This confrontation forces a resolution where Medhimama acknowledges her faults. After reconciling, Medhi's true personality emerges: she becomes mischievous, playful, and openly competitive, particularly challenging party member Wise, claiming superiority as a mage and seeking attention, especially from Masato. She displays protective instincts, threatening enemies targeting her party, and engages in light flirtation with Masato.

As a party Healer, Medhi uniquely wields her staff to deliver respectable melee damage against enemies. Her skills are demonstrated during dungeon explorations and combat, such as the tower quest confronting the anti-mother faction Ribele. Despite her magical prowess, she is a terrible cook; her mother previously used spells to disguise the poor quality of her food, a fact Masato discovers only after tasting it. In the OVA, she participates in beach activities and collaborates with Wise on schemes, like attempting to restore Masato's amnesia, though her plans often backfire comedically.