Ayumi, a sharp-tongued twelve-year-old with dry black hair framing her crimson eyes and lizard-like nails, moves through the world like a shadow slipping between cracks. Born to Spinner and Shigaraki, she shares a crumbling hideout that resembles a rundown hotel with her makeshift family: the blood-mimicking Toga who calls her Umi-cha, the winged fire-starter Miko, and young Kenji. Though she attends a hero academy during the week, her true loyalty lies with the criminals who raised her, where game nights bind them tighter than blood. Ayumi hungers to carve her own legend and earn her fathers' pride, yet the academy's rigid walls and bullies like Bakugo constantly thwart her. She retaliates with fights and time-shifting powers that let her rewind moments or drag foes through years, but the school's dorms isolate her from her true home except on weekends. Her rudeness wards off strangers, masking a fierce drive to prove herself in a world that demands heroism while she plots villainy. Conflicts arise from her double life, the odd gene that birthed her, and daily humiliations that fuel her rage. Each night she returns to the hideout, schemes brew, ensuring her path darkens further as she bends time to her will.