Sebas Tian

Sebas Tian (セバス・チャン) is the head butler of the Great Tomb of Nazarick with several manservants and other butlers under his command. He was created by Touch Me.

He is the Leader of the Pleiades Six Stars System. Although he is not one of the Floor Guardians, his power rivals theirs and he is independent from the Guardian's chain of command. He originally served as Nazarick's last line of defense in the ninth floor, to give time for the Supreme Beings to prepare for their final stand in the Throne Room.

Appearance
Sebas Tian has the appearance of an elderly butler and he is dressed gracefully in his traditional black uniform. His hair is entirely white, just like his immaculate beard. He has visible wrinkles on his hollow face, which makes him seem gentle in appearance, but his eyes are as sharp as an eagle's. However, in the manga his beard is longer, his shoulders aren't as broad and his face is also older.

Personality
Like his creator, Touch Me, Sebas Tian has a great deal of personal justice. Unlike many other denizens in Nazarick, he does not completely despise humans or see them as inferior creatures. Instead, he believes that some humans have a good nature and it is the duty of the strong to protect the weak. Ugly natured humans disgust him and he will not hesitate to kill anyone who dares to oppose Nazarick.

Due to the conflict in their personalities, he and Demiurge do not appear to get along well, as their characteristics are polar opposites.

The Undead King Arc
Sebas was the second person Momonga spoke to when he first arrived into the New World. His orders were to immediately survey the area around the Nazarick's surface above the 1st Floor after it was transported into the New World. He finds that the tomb is surrounded by grassland and the skies are completely normal, much to Momonga's suprise as he later reports this to all whom are present including the floor guardians on the 6th floor.

After Momonga returned from his surveying of Nazarick, Sebas lectured him sternly for not bringing his personal guards along. He stood by Momonga the entire time as he was experimenting with his Remote Viewing Lens, and praised him when he successfully figured out how to control it. However, when Sebas saw the massacre occurring in Carne Village, he couldn't help but feel obliged to help the villagers at the sight of the situation.

The Bloody Valkyrie Arc
While Ainz had been masquerading as an adventurer, Sebas and Solution have been ordered to disguise themselves as wealthy and influential humans to gather information. In particular, the roles they played were an elderly butler and a spoiled and rich noble.

At the Shining Golden Pavilion, Sebas acted as Solution's elderly butler while Solution acted as a spoiled rich girl. She then makes loud complaints about the food, giving everyone a bad impression of her. However, Sebas apologises for her behavior and offers to pay for everyone's meals. As they prepare to leave, Zach, a hired hand, attempts to delay the departure with a few excuses. Sebas sees through his treachery, and allows him to finish whatever he needs to do while their bags are being packed.

As the carriage goes on its way, Sebas engages in conversation with Shalltear, who has joined them on this segment of their journey. The two of them talk about her relationship with Aura, the old creators, the mystery of the eighth floor, and the job Shalltear was assigned to do. When the bandits targeting them have been lured out and destroyed, Sebas and Solution split off from her.

The Men in the Kingdom Arc
He rescues and nurses back to health a weak Tsuare.

When Sebas Tian is told to come to a warehouse alone due to Tsuare's kidnapping, four of the Six Arms were there waiting for him. They engaged him in combat but failed to even scratch Sebas and are killed. The other two were waiting elsewhere and encounter Brain Unglaus, Climb and Lockmyer. Succulent had disguised as Tsuare in an attempt to get them to let down their guard but fails and is defeated by Climb and Lockmyer. Zero and Brain engage in a fierce battle but are interrupted by Sebas. Not believing that Sebas could kill four of the Six Arms by himself, he puts his duel with Brain on hold and attacks Sebas with his strongest attack. It however, does nothing to the butler and Zero is killed with a powerful heel drop kick.

Trivia

 * He believed that it is wrong to cast out a pitiable existence simply due to possibilities of risk.
 * It is said that his appearance is the spitting image of how Touch Me looks like in real life.
 * In the WN, Sebas was not asked by Momonga for help on readjusting the Remote Viewing Lens.
 * In the manga, Sebas has a longer beard than in the anime.
 * Sebas mentioned that if he had to obey anyone orders without question it would be his creator Touch Me (but all the NPCs would follow their personal creators if they were still around).

Quotes

 * (To Momonga):"The person responsible for gathering us all. Compassionate and refused to abandon us until the very end, in order to stay behind and fight alongside us."