Chitose Saiga
Chitose is the younger brother of Yahiro and is about nine years old. He initially appears in (Chapter 13) Hawaii during the SA’s summer vacation when Ryuu (and by extension, the rest of the SA) is forced to entertain Chitose because he is the son of a client for his family. He is close to Ryuu, much to the chagrin of the twins, and it is implied that he has known Kei for a long time. Like his older brother, he dislikes poor people, which leads him to treat Hikari differently from others at first. However, when Hikari shows genuine concern for his well-being despite how badly he treated her, Chitose quickly becomes attached to her.