Solution Epsilon

Solution Epsilon (ソリュシャン・イプシロン, Solution・ε) is a member of the "Pleiades Six Stars", the battle maid squad of the Great Tomb of Nazarick.

Appearance
Solution is a blonde beauty with spiral curls and blue eyes, and clothing that emphasizes sex appeal. She is said to rival the most beautiful woman in Re-Estize Kingdom, the Golden Princess. As her race is slime, she can change her appearance as she wishes.

Personality
Solution thinks of humans as food and toys. She loves to swallow humans alive and enjoys the suffering and struggling of her victims. She does not like the screams of humans so she shuts her victims' throat with her body. She is, with Narberal Gamma, one of the two "extremely dangerous" Pleiades.

She is also good at disguising her nature, acting like a childish and rude lady when she was out to get information with Sebas. It seems that her true nature is quite logical, suggested by her complaint about inefficient behaviors of Sebas or Entoma.

The Undead King Arc
Solution along with her sisters are orders to guard the 9th Floor by Momonga. She and other Pleiades are on standby and waiting for Momonga.

The Bloody Valkyrie Arc
Solution disguise herself as a mistress from the Empire while Sebas Tian as her butler. In the Shining Golden Pavilion, she then makes loud complaints about the food, giving everyone a bad impression of her. She tells Sebas to ready the carriage and departure immediately. In the private room, she apologies to Sebas for her act and tells him about Zach's treachery. She tells Sebas that, she wants that human and Sebas replied that she need to ask permission to Shalltear Bloodfallen.

As the carriage goes on its way, She asked Shalltear's permission to devoured Zach which she agreed. When the bandits targeting them have been lured out, they slaughter them while Solution devoured Zach. She and Sebas split off from Shalltear, and continue there way to the Royal Capital.

The Men in the Kingdom Arc
and II Arc Solution welcome Sebas but notice that he brought a human with him and tells him that human may jeopardize their mission. Despite of this, she was ordered to heal the human and never report this to Ainz. After sometime a group of guards lead by Stafan Hevish and Succulent turns up accusing them of involving themselves with slave trafficking, and having bought Tsuare as a slave. Demanding them to pay a heavy fine and turn over Tsuare to their custody. After they left, she tells Sebas to dispose the human before it cause more trouble for their mission, After Sebas leaves, Solution finally decides to contacts Ainz and informing him that Sebas might have gone rogue.

She welcome Sebas back and tells him that Ainz Ooal Gown is waiting for him. After confirming Sebas's loyalty. She and Sebas prepare to return to Nazarick after buying wheat. Sebas tells Solution that Tsuare has been kidnapped and inform this to Ainz. Solution along with the Pleiades masquerade as Jaldaboath's battle maid during the Demon Invasion of the Royal Capital. She along with Lupusregina Beta and Entoma Vasilissa Zeta fight Narberal Gamma to make Momon a hero in Re-Estize Kingdom.

Trivia

 * Her race is based off of H. P. Lovecraft's Cthulhu Mythos.
 * She is willing to meet and face her superior, and someone a lot stronger than her with force if she felt that their actions disregards Nazarick's benefits or bring danger to Nazarick.
 * She is able to independently make decisions on her own when need to and even betray her superior if she felt that the person obstruct Nazarick's plans.

Quotes

 * (To Zach): "I am a preying type ooze. Time is limited, so I must swallow you now."
 * (To Shalltear): "Well, if I want to kill immediately I can emit a stronger acid, but it’s such a rare chance for a man wanting to enter me, so I want him to at least enjoy it for a day or two."