Pleiades

The Pleiades (プレアデス) is the combat maid squad of the Great Tomb of Nazarick. Its members originally only served as Nazarick's last line of defense, but Ainz has assigned them more tasks after the tomb was transported.

Background
The Pleiades is the combat maid squad of Nazarick, programmed as sisters. Unlike the other homunculus maids under the orders of Festonear S. Wangko, the Pleiades members do not have any skills for housework and instead fight under Sebas's command as a final raid boss team right before the throne hall. All of them are women of unsurpassed beauty, each with a different type of appeal. After the teleportation to the New World, three of them are working outside of the tomb. This seems to be because they are amongst the rare NPCs from Nazarick who can easily disguise themselves as humans.

The Pleiades can be organized in two different formations. One is the "Pleiades Six Stars" and the other is the "Pleiades Seven Sisters". These formations can be switched by changing the leader to Sebas or the Lastborn of the Pleiades. The "Pleiades Seven Sisters" activates in volume 6, yet Ainz does not allow the Lastborn to move and thus Yuri Alpha becomes deputy leader.

Strength
Considering them as a final boss of the Tomb of Nazarick, the Pleiades's combat capability is quite low, all of them except Sebas being under level 65. This is because the substantive final defense line of Nazarick is in the 8th floor. The actual role of the Pleiades is just to delay the invaders and allows all the guild members to gather in the throne hall to greet the invaders like villains in fiction. However, the low power level in the new world makes them equivalent to legendary monsters.

Members

 * Sebas Tian - Leader of Pleiades Six Stars System
 * Yuri Alpha - Deputy Leader
 * Lupusregina Beta
 * Narberal Gamma
 * CZ2128 Delta
 * Solution Epsilon
 * Entoma Vasilissa Zeta
 * Lastborn of Pleiades - Leader of Pleiades Seven Sisters System

Trivia

 * The dual organization of the Pleiades refers to two different meanings of the word "Pleiades". In Greek mythology, the Pleiades are seven sisters, daughters of the titan Atlas, while in astronomy the Pleiades is a star cluster called in Asia the "Six Combined Star" (六連星).
 * The homunculus maids of Nazarick think of the Pleiades as a kind of idol group. Among them CZ is the most popular.