Mabayu Aki, a 15-year-old magical girl from Mitakihara City, attends Mitakihara Middle School as a third-year student while living with her aunt, Sakie Aki, at the café Récompense, where she assists with daily operations. Her mother, gifted with future sight, succumbed to a terminal illness she herself foresaw, driving Mabayu to wish away all memories of her mother’s prophecies. This wish bestowed powers to manipulate memories by visualizing them as editable film reels and to bend light for invisibility or heightened vision.

Mabayu perceives and navigates time loops, retaining awareness through Homura Akemi’s timeline resets. Armed with golden scissors and a purple, camera-lens-shaped Soul Gem on her left hip, she allies with Homura across cycles to thwart Madoka Kaname’s transformation into a witch, frequently sacrificing herself to shift outcomes. In one timeline, she excises Nagisa Momoe’s memories of murdering Mami Tomoe and Kyoko Sakura as Charlotte, striving to spare Nagisa from guilt.

A dedicated cinephile, Mabayu frequents cinemas and video stores, framing her battles through metaphors of film editing. Despite social awkwardness hindering personal connections, she covertly influences events, observing figures like Mami and Homura from afar using her magic to eavesdrop or surveil.

Her design blends green hair, purple eyes, and a golden hairpin evoking clock hands or scissors. Debates surround her inconsistently depicted hat—sometimes a crown, sometimes a cap—while fan theories tie her to Walpurgisnacht through shared motifs. She occasionally summons spectral echoes of past magical girls, mirroring Witch Itzli’s abilities.

Across timelines, Mabayu’s efforts underscore her struggle to aid others while enduring the emotional strain of cyclical failures. Her narrative weaves themes of memory alteration, the weight of foresight, and the ethical shadows cast by unseen interference in others’ lives.