Kouichi is a young man, approximately 175cm tall, and 15 years old. Kouichi has fair skin, short brown hair and brown eyes. His clothes range from a blue turtleneck shirt to a sweater, pants, and sneakers. Kouichi is the oldest brother of three; Sayuri Tsujii (middle sister) and Souichi Tsujii (younger brother). His hobbies are studying and spending time with his family.