Yuko

Of roughly average build and a touch shorter than Asa, Yuko keeps her pale blonde hair cropped close, her eyes a matching light shade behind tinted glasses. At school she dresses like her classmates in the pinafore uniform with knee socks and sneakers, swapping in a plain shirt, dark jacket, cropped jeans, and sandals on her own time.

Her contract unlocks far stranger shapes. She can warp into a lean, skeletal thing whose brain sits exposed while tendrils take the place of legs. Cut down once and revived, she balloons into a towering horror, a single transformed head ringed by writhing limbs large enough to swallow several stories of the school. Her final state is a Devil proper, human in outline with the old blonde hair, but threaded by fine tendrils that mask her eyes without blinding her, her arms and legs wound in the same growths like a clinging gown she hides under a hood.

The face Yuko shows the world is gentle and outgoing. She befriends Asa almost at once, moved by the way classmates shun the girl over Bucky's death, and she presses kindnesses on her, famously surrendering her own shoes. Avenging parents lost to Devils fuels her ambition to hunt, as does the money the work promises, and a shared grief knits her tightly to Asa. By her own account she struggles to grasp other people and has gone friendless because of it.

That warmth masks a chilling interior. Yuko kills those she judges wicked without a flicker of guilt, smiling all the while, her morality bent around the belief that good intentions excuse any act. Convinced she had bargained with the Justice Devil, she slaughters a neighbor and offers to erase Asa's tormentors, certain that fear of her example will deter cruelty nationwide. That very sense of right and wrong was likely warped by the contract as its true cost. Late in her story she softens into regret, admitting she only craved the fame of Chainsaw Man and first approached Asa out of loneliness, yet the friendship she found turned genuine all the same.

Once teamed with Asa in the Devil Hunter Club, she gushes about her love of Chainsaw Man and grows inseparable from her new partner. The two learn their parents were both taken by Devils, and a reincarnated Bat Devil nearly devours them before Chainsaw Man intervenes. Yuko soon confesses to a killing, reveals the mind-reading pact she believes ties her to the Justice Devil, and vows to settle Asa's bullying problem herself.

When she transforms and rampages through the school, picking off those she brands bullies, Asa finally turns a weapon on her and cuts her to pieces. Fami resurrects her into a colossal monster that bursts through the building, until Denji arrives as Chainsaw Man and shreds the form. Yuko endures the night as a newly made Devil, returns to Asa's home to apologize, and trades the old joke about the shoes one last time before parting. Not long after, a figure wearing Chainsaw Man's likeness finds her and takes her head.