Katsuki is a young gir of average height, with a slim, muscular build, and a fair skin tone. She has short, spiky, sandy blond hair with choppy bangs that hang over his eyebrows. Her eyes are sharp and bright red in color.

At school, she wears the standard U.A. uniform without the customary red tie. Underneath her blazer, she wears a white collared shirt with the top few buttons undone. Her pants are worn loosely, causing them to sag at his ankles, despite her wearing a belt with them. 