Maria is a half-demon girl born from the union of the former Demon Lord and a human woman. She sealed her father and the rest of her demonic species in the underworld, an act that shapes much of her identity and motives. To control her overwhelming demonic power, she wears shackles that suppress her strength. She also houses a fierce alter ego named Mao, who exists as a separate personality and is a student in a lower class at Rosewood Academy. Physically, Maria is a female teen with gray eyes and long purple hair that reaches chest length, and she has pointed elf ears. Her personality is initially defined by a strong and immediate interest in the hero Blade after he defeated her father; over time this interest deepens into genuine affection and eventually romantic love. She seeks redemption for her past deeds and finds purpose and emotional connection through Blade. Her role in the story is that of a supporting student at Rosewood Academy, and she appears prominently in episodes dealing with the Demon King’s daughter. Her most important relationship is with Blade, whom she cares for deeply, and she also grapples with the coexistence of her alter ego Mao. Through her interactions with Blade and her struggle to master her dual nature, Maria undergoes personal growth, moving from a conflicted demonic heir toward a more stable and loving individual. Her notable abilities include vast demonic power that is deliberately restrained by her shackles, as well as the latent abilities of her alter ego Mao.