Saiyori is she\her and Kasu is they\them. Saiyori has White hair to her waist and Kasu has black hair to their calves. Saiyori looks happy and healthy while Kasu looks dead and sick. Saiyori is loud and cheerful while Kasu is emotionless and truthful. They are both wearing their school uniforms and are always together. Everyone at their school thinks that they could be dating because they are always together but they are just together as friends and always will be.