Undertaker

An associate of the Phantomhive family, the Undertaker. A man with long silver hair, dressed in black, who speaks in a creepy tone. His eyes are hidden by his bangs, and he refers to himself as "this humble one." His real name is unknown, and as his nickname suggests, he runs a funeral parlor in London. He has been a collaborator with the Phantomhive family for a long time, undertaking tasks such as gathering information and performing autopsies as a funeral director. He demands laughter as payment for information or work, a quirk even Sebastian acknowledges. It is revealed in the "Luxury Liner Arc" that he is a reaper who has left the Dispatch Society and is involved in events related to "Bizarre Dolls." From then on, he is pursued by Ciel while also showing an obsession with Ciel and the Phantomhive family.

His true identity is that of a reaper who left the Dispatch Society half a century ago, referred to as a "violator" by the society. He has the characteristic lime-green phosphorescent eyes of a reaper but does not wear glasses. He possesses a "Death Scythe" in the form of a large scythe and is skilled in using countless memorial tablets as auxiliary weapons. He also has physical and combat abilities that rival Sebastian's.

During his time with the Dispatch Society, he belonged to the retrieval division and was considered a model reaper who performed his duties perfectly, according to his colleague Othello. However, about 70 years ago, he caused half of the society to be destroyed and fled, becoming a legendary fugitive.

He is the mastermind behind the "Luxury Liner Arc" and the "Public School Arc," creating "Bizarre Dolls" and experimenting with what would happen if the continuation of Cinematic Records were inserted into bodies emptied of souls after soul collection. In the "Luxury Liner Arc," the result was akin to zombies without self-awareness, but in the "Public School Arc," by connecting individual episodes, he managed to awaken something resembling self-awareness in Agares, allowing for a semblance of daily life. His true goal was the revival of the real Ciel, and it turns out that on the day Sebastian was summoned (the day the real Ciel died), he secretly collected the body and continued revival measures. He wears a pendant containing the hair of Ciel's grandmother, and from his statements that "Vincent cannot be brought back because he turned to ash" and "I do not want to lose Phantomhive anymore," it is implied that his obsession is not with the individual Ciel but with the Phantomhive family as a whole. In the "Blue Cult Arc," he finally revives the real Ciel with self-awareness by replacing his blood.

In the anime version, from episode 18 of the first season, it is revealed that he was a legendary reaper who had dealt with the souls of famous figures like Marie Antoinette and Robin Hood. Although he is now retired, he was a management-level officer during his active duty, capable of handling the final weapon (Death Bookmark), which is beyond the authority of Will or Grell.