Sebastian Michaelis, the demon butler of the Phantomhive household, is a striking figure known for his tall, handsome appearance. His sleek black hair complements his reddish-brown eyes, which add to his mysterious allure. His skin is pale, and he has distinctive black fingernails, with the mark of his Faustian contract with Ciel Phantomhive etched on the back of his left hand.

As a butler, Sebastian dresses in a classic, formal black suit. His attire consists of black trousers, a six-buttoned double-breasted tailcoat, and a gray vest, all of which reflect his impeccable taste and professionalism. His shirt cuffs and tie are adorned with the Phantomhive crest, and he wears white gloves, a pocket watch, and a silver lapel pin, all traditional accessories for the head butler of the Phantomhive estate. These elements emphasize his role and his commitment to serving Ciel.

When in his demonic form, Sebastian’s appearance shifts dramatically. His once human features are replaced with dark, sinister attributes: high-heeled stiletto boots, sharp claws, glowing fuchsia irises, slit pupils, and longer, sharper teeth. Additionally, he grows dark wings and multiple eyes, which are a representation of his true demonic power and form, marking the stark contrast between his charming human disguise and his fearsome, otherworldly nature.

Sebastian Michaelis is a demon butler whose devotion to Ciel Phantomhive is unwavering, and he diligently carries out every order with precision and grace. As the head butler of the Phantomhive estate, Sebastian ensures that all operations run smoothly, displaying impeccable professionalism. Demons do not require sleep, and Sebastian fully embraces this, often staying up through the night to complete his duties. Despite his apparent loyalty and flawless performance in his role, he is occasionally critical of Ciel’s treatment of his staff, revealing a small, human-like tendency toward concern for others, though he hides it under his usual composed demeanor.

While Sebastian’s butler persona is flawless, he is, in reality, a sadistic demon with no qualms about using his powers to carry out ruthless and sometimes cruel acts when following Ciel’s orders. He has no hesitation in putting Ciel in dangerous situations for his own amusement, but always with the expectation that he will be there to rescue him. This confidence stems from his superior abilities, though he occasionally expresses concern when the situation becomes too dire for Ciel’s safety, especially when the threat is from other formidable characters like Angelina Dalles or the Undertaker.

Sebastian’s cunning and morally bankrupt nature mean that he will go to great lengths to secure his goal—ultimately, to claim Ciel’s soul. He is ruthless in his pursuit, showing no hesitation to deceive, manipulate, or use others for his gain. Despite his lack of genuine empathy, Sebastian is fascinated by humans and their insatiable desires, seeing them as “difficult creatures” for their relentless drive to get what they want, even at the cost of others’ well-being.

Though he is not one for materialism, viewing money as “rubbish,” Sebastian shows a more whimsical side through his adoration of cats. His fondness for the creatures is so great that he once secretly kept thirteen hidden in his wardrobe, much to Ciel’s oblivion. His multilingual abilities, including fluency in French, Latin, German, and East Franconian, further exemplify his cultured and refined nature, often serving as a tool for both education and manipulation in his quest to carry out his duties—and, ultimately, to achieve his demonic objective.

Sebastian Michaelis, a demon from an alternate world, has lived for a long period of time, far longer than any human, and often reflects on the fleeting nature of Ciel Phantomhive’s life in comparison to his own. His background is mysterious, and he has had a long history of consuming various souls, having once indulged in “sampling every dish available” before deciding to focus on consuming “high-quality” souls. This choice, he claims, has left him somewhat starved, but he views his hunger as an added benefit, as it makes the “dinner” even more satisfying when he finally claims a soul.

In 1886, Sebastian was summoned to Ciel through a cult’s ritual in a cathedral. After forming a Faustian contract with Ciel, sealing it with a mark on Ciel’s right eye, Sebastian’s role was set: he would serve as Ciel’s butler, protecting him and aiding him in his mission of revenge against those who wronged him. In return, Sebastian would claim Ciel’s soul once the boy had completed his vengeance. Sebastian then burned down the cathedral on Ciel’s orders, setting the stage for the two to work together.

After their first encounter, Sebastian accompanied Ciel to meet his aunt, Angelina Dalles, at the Royal London Hospital. While Ciel mourned the loss of his family, Sebastian used his demonic abilities to rebuild Phantomhive Manor. Sebastian became a dutiful butler, teaching Ciel the essentials of his new life as the Earl of Phantomhive. Despite his demonic nature, Sebastian acted as a mentor, helping Ciel navigate his new responsibilities and sometimes having to discipline his spoiled behavior.

Sebastian’s loyalty to Ciel was ed when Ciel hesitated during their walk to the coronation. At that moment, Sebastian nearly devoured Ciel’s soul, but he stopped when Ciel, showing a renewed sense of purpose, commanded him to be his sword and shield in the pursuit of revenge. The promise of the immense pain and suffering that would accompany Ciel’s quest for vengeance made Ciel’s soul even more delicious in Sebastian’s eyes.

Sebastian’s devotion was further proven when he recruited servants for Ciel, including Baldroy, a former American soldier. Over time, Sebastian came to understand Ciel’s true desire for revenge, and he fully embraced his role as Ciel’s servant, even though it meant enduring the physical and emotional toll that came with Ciel’s ambitions. Despite his often cold and calculating demeanor, Sebastian showed moments of amusement and affection, particularly with his spoiled but nonetheless determined young master.

• Ciel Phantomhive
  As Ciel’s butler, Sebastian is both servant and protector, carrying out his master’s orders with precision. Their relationship is marked by a blend of mutual respect and manipulation, with Sebastian constantly reminding Ciel of the ultimate cost of their contract.

• Phantomhive Servants
  Sebastian often mocks the eccentric staff of the Phantomhive household for their incompetence, though he steps in to maintain order and efficiency when needed. Despite his disdain, he occasionally demonstrates a begrudging tolerance for their loyalty to Ciel.

• Antagonists and Supernatural Beings
  Sebastian frequently encounters other demons, Grim Reapers, and supernatural entities, showcasing his superiority in combat and intellect. His interactions with figures like Grell Sutcliff and Undertaker reveal more about his demonic nature.

Sebastian Michaelis is one of the most iconic characters in Black Butler, embodying the series’ themes of loyalty, manipulation, and the allure of the supernatural. His flawless butler persona contrasts with his sinister demonic nature, creating a character of immense depth and intrigue. As Ciel’s constant companion and protector, Sebastian’s role in the story blends action, mystery, and dark humor, making him a fan-favorite and an enduring figure in anime and manga.