Myu, a young dagon girl, first emerges during a kidnapping in Fuhren, rescued and adopted into the protagonist’s family after her biological father’s pre-birth death. Her fierce attachment to her rescuer shifts from calling him “Onii-chan” to “Papa.” Distinctive dagon traits mark her appearance: fan-like fin ears, webbed extremities, emerald-green hair, and sky-blue eyes, complemented by a white frilly dress adorned with blue ribbons, orange sandals, and a star-shaped hairclip.

Once prone to tantrums and spoiled behavior, the kidnapping’s trauma accelerates her maturity, though flickers of her former self surface within her adoptive family. She adopts otaku passions—anime, video games like *Monster Hunter*—mirroring her adoptive father’s hobbies, while growing desensitized to ghosts yet harboring a lasting desert phobia.

Relocating to Earth ignites a militaristic streak: she adopts a drill-sergeant persona in conflict, espousing mercilessness toward foes. Her supernatural charisma effortlessly forges alliances with humans and mythical beings like kappas or UMAs, often sparking rivalries among admirers. Trained in defensive combat, she wields twin kodachi swords (Muramasa, Kotetsu), revolvers (Donneer & Schlaag), and the Schlaagen rifle, pilots the Overanger mecha alongside the Demon Rangers—golems housing the Seven Princes of Hell—and employs a magic pendant, aerodynamic boots, and an interdimensional smartphone with emergency healing functions.

A pivotal OVA adventure sees her family ally with historical Liberators in a ruined city, bridging timelines and showcasing her tactical growth. Central to her journey is her bond with mother Remia, who navigates guiding Myu’s upbringing while curbing external influences. Myu’s independence drives her to aid others recklessly, yet criticism of her adoptive father triggers tearful vulnerability, swiftly soothed by his comfort.