Mao is a student at Rosewood Academy and a secondary character in the anime Classroom for Heroes. She is one of two distinct personalities sharing a single body with a girl named Maria. While Maria is the original personality, shy and submissive, Mao represents a more abrasive, assertive, and confident side. Mao is openly attracted to the protagonist Blade, and her demeanor contrasts sharply with Maria's timidity.

Mao is the reincarnation and self-proclaimed daughter of the Demon King, which gives her a unique heritage within the academy's setting. She is a member of a lower class at Rosewood Academy and is characterized by her striking appearance: very long purple hair, red eyes, elf-like ears, and wings. Her motivations stem from her demonic lineage and her developing feelings for Blade, leading her to engage with the main cast in both supportive and competitive ways.

In the story, Mao plays a role in exploring the themes of identity and duality, as she and Maria must learn to coexist. Over the course of the series, the two personalities gradually reconcile and find harmony, with Mao's blunt nature softening as she grows closer to the other characters. Her notable abilities are tied to her demonic origins, though specific powers are not extensively detailed; she is portrayed as having supernatural traits such as her wings and enhanced physical capabilities. Her relationship with Blade is central to her personal development, and she interacts frequently with the other hero candidates, often displaying a competitive yet caring attitude toward them.