Sengoku is a slim pale-skinned young man with smooth red hair that is parted towards the right side, completely covering both his ears and red eyes. He is almost always seen wearing a sweater over his school uniform, occasionally taking it off or wearing his blazer. Due to his skinny figure, he usually needs to wear multiple layers of clothing to appear of a healthier weight. This, along with his unusually high voice, makes him appear somewhat feminine.