Sayaka Hozumi

In the visual novel, Sayaka is a deputy librarian in the royal moon museum. Tatsuya and Mai refer to her as their older sister, although she is actually their cousin. In the anime, Sayaka is the primary secretary to the president of the United Nations so in effect has a lot of ties with the politics that is involved between Earth and the Kingdom of Sphere. Her nickname in the media is the "President's Dagger".