Cocytus


 * "Fifth Floor Guardian Cocytus, at your command."
 * - Cocytus' Introduction

Cocytus (コキュートス) is the floor guardian of the fifth floor in the Great Tomb of Nazarick. He is a hybrid between a mantis and an ant. He was created by Takemikazuchi.

Appearance
Having an enormous body size of 2.5m, Cocytus has the appearance of an insect walking on two feet - a fusion between a mantis and an ant.

With a tail twice as long as his height, Cocytus is covered with sharp spikes like icicles and has a strong jaw that can easily snap people's hands. Two of his hands hold a silver halberd, while the remaining two hands hold a mace emitting black light and a crooked shape sheath which seems to be for a broadsword. With a breathtaking cold air, the pale blue, hardened bone armor oozes out diamond dust like bright light. His shoulders and back look like an uplifted iceberg.

Personality
Cocytus has a warrior personality and respects anyone with a fighting spirit and the heart of a warrior. As Floor Guardian, he's in charge of Nazarick's martial defense, Cocytus seem loyal to a fault. As shown when he prevented Demiurge, under Ainz's order, from interfering in Ainz's fight against Shalltear even though he too also feared the possibly of losing his master.

A warrior by heart, he likes a good battle and has a sense of honor. Unlike his isolationist and xenophobic colleagues he is more accepting in allowing outsiders join Nazarick. Though he takes pride in his position as Nazarick's defender, he is somewhat envious of his fellow Guardians. He likens himself as the 'sword' of Ainz Ooal Gown, that executes his master's wishes and thinks the only way he could prove to Ainz his worth is by actually defeating the invading forces that would be a threat to Nazarick. Cocytus isn't fond of asking for assistance in order to save face, but when the need arises he will put his pride aside to accomplish his task.

The Undead King Arc
When Momonga calls for the floor guardians to the sixth floor, Cocytus is the second to arrived. He stops the argument between Aura and Shalltear in front of their master. After all of the guardians arrive, he pays his respects with the rest of them to Momonga.

The Bloody Valkyrie Arc
Cocytus was ordered to restraint Demiurge from interfering the fight between Ainz and Shalltear. When Ainz emerges victorious from his battle, Cocytus and the other floor guardians beg him to never do such a thing again, and to allow them to handle any future incidents that may come.

The Lizard Man Heroes
Cocytus was ordered to annihilate the Lizardman which failed. Cocytus is surprised at his defeat and shamed at losing. He has no choice but to return to Nazarick, however, he is deeply impressed by the lizardman. After his failure, Cocytus asks Ainz if they could spare the lizardman and make them as part of Nazarick which Ainz agreed.

To redeem his failure, Cocytus fights against the lizardman heroes lead by Shasryu Shasha, Zaryusu Shasha and Zenberu Gugu. Cocytus kills all of them by his hands. Cocytus emerges victorious from his battle against the lizardman, He is now in-charge of the occupation of the lizardman tribes.

Trivia

 * The name "Cocytus" is a reference to Dante's Inferno, in which Cocytus is the ninth and final layer of Hell. It is referred to as a frozen lake that houses all of humanity's traitors.
 * In the web novel, he was put in charge of the security from 9th floor to the 10th floor.
 * One of his hobbies is collecting unique and foreign weapons.

Quotes

 * (To Momonga): "More powerful and stronger than any Guardians. Supreme ruler of the Great Tomb of Nazarick."
 * (To Aura): "A sword does not think, swung to the will of its master, it only cuts."
 * (To the lizardmen): "This might be rude for the warriors who came with the resolve to die, but know this, only death awaits all who cross beyond these ice pillars."