Kiyume is a short girl, approximately 150 cm (4'11") tall, with shoulder-length hair and large violet irises. She is 15 years old and attends high school. Kiyume wears the school's summer uniform: a white long-sleeved shirt with the school logo, a navy blue skirt, and school shoes. She often has bruises and bandages. She has a twin sister named Siyume. Siyume is also short with dark brown hair and large, bright yellow eyes. She wears the same school uniform. Siyume is described as emotional and enigmatic, often causing trouble at school. Kiyume has no friends and is often injured. She refuses to reveal who is responsible for her injuries.