William is an agent from Tsukikage, and also is working for the Yakuza in Nippontown, Chicago. He is also a martial arts and kendo instructor at a dojo besides the Moon Temple.
Book 1: The World Awakens
He was dating Regina Cruz, a member from Ordo Aureum Aurora that stole the Codex Draco Rubrum from Ashley Alafousus. William was approached by Kanako Sakai when she and her Band was investigating about the stealing of the book, and warned him that the Yakuza are unhappy about his affairs. After the events from Red December, he and Regina broke up their relationship. He is still a member of the Tsukikage in the city.