Kana Umeno, a kind and mild-mannered classmate of the protagonist, dedicates herself to preserving their happiness, carefully navigating the protagonist’s quick-tempered nature. Her appearance features short dark brown hair, large black eyes, and a vibrant outfit: a red shirt boldly displaying "Fine" across the front, paired with blue shorts, yellow socks, and sky-blue shoes. Though deemed a social outcast by peers, Kana consistently demonstrates loyalty, defending her friends with quiet resolve. Her well-intentioned support sometimes leads to unexpected mishaps, particularly when the protagonist’s volatile transformations inadvertently involve her. Their friendship, marked by mutual reliance and occasional chaos, remains central to her role within their shared experiences.