Sebastian Michaelis

The protagonist of the work. The butler of the Phantomhive family. Black hair. His eyes are the color of black tea. Height is 186cm. He is a person who is perfect in every aspect including dignity, education, martial arts, cooking, and appearance. Despite his abilities, he is extremely humble and polite, but that does not necessarily reflect his inner thoughts. He can be sarcastically rude, even towards his master, Ciel. He maintains his polite demeanor towards Finny, Mey-Rin, and Baldroy, who often cause disastrous messes, but he internally curses them for their repeated failures. He loves cats (including feline animals like tigers), especially pressing their paw pads.

His true identity is that of a demon. He effortlessly performs skills that are impossible for humans, and attacks that would be fatal to humans have no effect on him. He has made three contracts with Ciel: "not to lie to him," "to be utterly loyal and never betray," and "to protect him from all external threats until his revenge is complete," with a reverse pentacle symbolizing black magic on the back of his left hand. His current appearance was chosen to match Ciel at the time of their contract, but initially, he was unable to fulfill any of Ciel's demands as a butler and was branded a "fake." After numerous corrections and training from Ciel, he has become the perfect butler he is now.

His catchphrases are "I am simply one hell of a butler," "What kind of butler would I be if I couldn't do this much?" and "Yes, my lord." The name "Sebastian" was taken from the name of a dog previously owned by the Phantomhive family, and his name before that is unknown. During the Noah's Ark Circus arc, his stage name while infiltrating the circus was "Black." He owns a dog named "Cerberus," who has not appeared in the main story.

The author refers to him as "Sebas." Originally, his hair was designed to be parted 7:3, but it was changed to a center part due to various reasons.

In the anime version:

He dislikes dogs. In the final episode of the first season, he reveals his true form (which he describes as "grotesque, ugly, and ghastly") while slaughtering Angela (Ash), but except for his heel-like feet, his form is shrouded in black shadows.

In the second season, due to the contract between Alois and Hannah, Ciel is transformed into a demon, causing him to lose his human soul, and Sebastian can never consume his soul. Furthermore, because of Ciel's order to "serve as a butler until he consumes his soul" and his command in the Labyrinth of Roses to "be my butler forever," to which Sebastian replied "Yes," he is fated to serve as Ciel's butler forever. In the final episode, he returns the pin, a symbol of being the head butler, to Tanaka, and leaves the mansion with Ciel. His catchphrase changes from "I am simply one hell of a butler" to "I am simply a butler, a demon butler."