William is an employee in the Dispatch Management Division of Death Gods. He makes his appearance in chapter 12 of manga or episode 6 of anime to pick up Grell Sutcliff. Despite being emotionless and generally calm, he follows rules strictly and appears very dedicated to his job. He dislikes individuals who cause problems or increase workload for him, especially if it requires him to apologize. Although he shares Ronald's aversion towards overtime work, he doesn't hesitate to inflict minor injuries on others as demonstrated when he jumps off a roof onto Grell Sutcliff's head and uses his death scythe to attack Sebastian on several occasions. He considers demons disgusting creatures and often refers to Sebastian Michaelis as "devilish fiend," "leech," and "hound." However, it seems that he finds other demons even more repulsive than Sebastian. In the anime, William works with Sebastian more willingly, helping him on multiple occasions. Nevertheless, he doesn't seem fond of anyone, as Ronald notes that he is unhappy to see him, and he insults various individuals including Grell, Sebastian, and Ciel Phantomhive.