- "The Seventh Floor Guardian Demiurge, at your command."
- - Demiurge's Introduction
In the New World, under the guise known as Jaldabaoth, a powerful Demon Emperor that led his demon army to starts a disturbance in the Royal Capital of the Re-Estize Kingdom and also led the demi-humans coalition to assault on the Roble Holy Kingdom.
About 1.8m tall, Demiurge is a demon with dark skin, and nicely combed black hair. Behind the round glasses are eyes so squinted that they aren't normally visible. Wearing a British suit with a tie, he is dressed like a gentleman. Behind his back is a silver tail, covered with metal plates and six long spikes at the end.
Demiurge's pair of eyes lacked eyeballs. In fact, it was completely without pupil or iris, but were shining jewels with numerous small cuts.
As a member of the Demon race, Demiurge is considered to be one of the cruelest members in Nazarick, taking great joy in the suffering of other races. For that reason, he enthusiastically performs magic experiments on the prisoners sent to him, viewing them as nothing less than toys for his own amusement. In other words, he enjoys inciting hateful feelings and treacherous thoughts among the victims of his experiments with a passion. Being the Commander of the NPC Defenses, he has a high level of intelligence and strategic thinking.
Demiurge works closely with the other servants of Nazarick and is loyal to the creators, thinking of them as important companions. However, due to their conflicting personalities shared with their respective creator, he and Sebas Tian do not appear to get along well with each other. Though he is a sadistic demon that thrives on the pain of other creatures, he has a more artistic side to him. He is a skilled carpenter and artisan, with hobbies of crafting beautiful works of art. Such artwork is done by him through using victims from his experiments as tools for making one.
On the other hand, his kindness was genuine when it was directed to his fellow denizens of Nazarick. He was considered to be a very gentle person when it came to conversing with his friends. However, to everyone else, his kindness was merely the care he gave to his tools.
Demiurge was created by Ulbert Alain Odle as one of the Floor Guardian of the Great Tomb of Nazarick.
The Undead King Arc
- Main article: The Undead King Arc
When Momonga calls for the Floor Guardians to the sixth floor, Demiurge was the last one to arrive. After paying his respects to the Supreme Being, he ponders about the future of Nazarick. More so, wondering if whether or not Momonga will leave a successor to carry the throne.
While waiting for Albedo on the first floor, Demiurge discovers Momonga attempting to sneak out of the tomb in a dark warrior outfit. Persuading him to take one person along, he accompanies his master as they appreciate the world around them. When Momonga jokes about conquering the world, Demiurge seriously offers to ready the armies of Nazarick to present it as a gift.
After Momonga announces his goals to the NPCs, Albedo has Demiurge relay the words Momonga imparted to him earlier. Misunderstanding Momonga's true intentions, he tells everyone present that their master's wish is to claim the world for the glory of Nazarick.
The Emissary of the King Arc
Upon receiving the messenger from Ainz who relays the question on what Demiurge desires. The demon humble stated that serving the will of his master to be fulfillment enough and questions whether this is a test. He then decides that he would desire to become the marshal of the skies once Ainz's plans for world conquest comes to fruition.
The Dark Warrior Arc
- Main article: The Dark Warrior Arc
Having been given a mission by Ainz, Demiurge proceeds to find Albedo to announce his departure. Understanding of her nature, he immediately goes to Ainz's bedroom and finds Albedo squirming under the sheets. Listening to her delusions of having Ainz's children, he gives her a tip that the Supreme Beings like boys to wear girls' clothes due to a previous misunderstanding. Exasperated and uneasy, he notifies her of the other Floor Guardians' absence and the human experiments being conducted on the Sunlight Scripture before leaving.
The Bloody Valkyrie Arc
- Main article: The Bloody Valkyrie Arc
Shocked and angry after discovering that Ainz intended to fight Shalltear, Demiurge berates Albedo for letting him go alone. Extremely worried that Nazarick may lose its last master, he tells her and Cocytus that they must bring him back by any means necessary. He declares that he will gather his men to do so, but was stopped by Cocytus, who was ordered to restrain him. Enraged, he tells Albedo that she must resign from her position as Overseer if anything were to happen to Ainz.
When Ainz emerges victorious from his battle, Demiurge and the other Floor Guardians beg him to never do such a thing again, and to allow them to handle any future incidents from now on.
The Lizard Man Heroes Arc
- Main article: The Lizard Man Heroes Arc
Demiurge along with the other Floor Guardians threatens and intimidates the lizardman, so that they become a part of Nazarick. He uses his magic to forcefully make Shasuryu Shasha and Zaryusu Shasha bow down in front of Ainz Ooal Gown.
The Two Leaders Arc
- Main article: The Two Leaders Arc
He and the other male Floor Guardians go for a bath together. However, midway through, Albedo and Shalltear attempt to get in and are assaulted by the Lion Golems. As a result, Ainz and the male Floor Guardians prepare to help them, wishing a peaceful bath the next time they have another one.
The Dark Hero's Story Arc
- Main article: The Dark Hero's Story Arc
The Men in the Kingdom Arc
- Main article: The Men in the Kingdom Arc
When Solution reported Sebas' possible betrayal, Demiurge is the one who suggested that they take caution and have Pandora's Actor masquerade as Ainz in order to test Sebas' loyalty. He is present along with Victim and Cocytus in testing Sebas' loyalty by ordering him to kill Tuare while having Cocytus confirm if he's delivering a killing blow. After that, he had a bit of quarrel with Sebas concerning Tuare's fate, which made Ainz remembered about Touch Me and Ulbert's quarrels in the past. Also, Demiurge, with Ainz' approval, went to investigate something strange Sebas' detailed in one of his reports (Possibly concerning the Golden Princess).
When Tuare is kidnapped, Demiurge brought Entoma, Mare, and Shalltear along with his Evil Lords to punish the Eight Fingers and to initiate Operation Gehenna, where he was appointed as the commander. At this time, he told all Nazarick forces gathered in the capital to spare one human (possibly Climb) and sent Nazarick's forces to attack several locations, including a new location added at the last minute.
Demiurge, as Jaldabaoth, also saved Entoma before she was killed by Evileye, Gagaran and Tia. Using Evileye as the standard for measuring their group's strength, he launched an attack that immediately killed both Gagaran and Tia. Before he finishes off Evileye, Momon stepped in and confronted him. He later retreated after giving false information to Evileye and exchanging several blows with Momon. He then raised a wall of fire, Flames of Gehenna, on the capital's warehouse district, and have his Evil Lords summoned a demon army, kidnapping the citizens and raiding the storehouses.
When he engages Momon again in combat, they arrived at a location that was prepared beforehand where they put aside their charade and discuss Demiurge's plan. His plan was to attack Eight Fingers while covering their tracks using Jaldabaoth as a cover. Also, for additional means of obtaining great amount of resources, capturing humans as well as to raise Momon's fame in the Kingdom. He was about to leave an item containing the 10th tier spell, "Armageddon Evil" to serve as Jaldabaoth's purpose of invading the capital, which is created by his creator, Ulbert. However, Ainz gave him another item to replace it, which is the prototype of the previous item made also by Ulbert to serve as the decoy instead. At last, the two continue their battle from where they left off, with Momon seemingly winning the battle against him. Thereafter, Jaldabaoth then withdrew his forces and Momon became the Kingdom's national hero.
The Invaders of the Large Tomb Arc
- Main article: The Invaders of the Large Tomb Arc
In the Great Tomb of Nazarick, Ainz gathers all of the custom NPCs and strong servants in the Throne Hall. From the convention, Demiurge emphasizes their final objective: taking over the world and suggests to make Nazarick an independent nation which goes by the name of the Sorcerer Kingdom.
The Magic Caster of Destroy Arc
- Main article: The Magic Caster of Destroy Arc
Demiurge, in his imp form, was present in the Throne Hall, during the visit of the Baharuth Empire's delegation. During the negotiation, Ainz charged him to act as Nazarick's ambassador. After the delegation left Nazarick, Ainz and the Floor Guardians held a meeting and listened to Demiurge's insight of how the emperor is planning to betray them.
The Ruler of Conspiracy Arc
- Main article: The Ruler of Conspiracy Arc
Demiurge has returned from the Holy Kingdom and intends to meet up with Ainz, only to find Albedo in his office. Demiurge is shocked that the Empire sent a petition, offering to be vassalage to the Sorcerer Kingdom which is a lot earlier than he expected. While the best method that he could devise to make the Empire a vassal state required the estimated time span of at least a month, Ainz took three days at most with no apparent casualties no less, which left Demiurge almost speechless and in total awe. Subsequently, it motivated him to work even harder and affirming his belief that there was no other Supreme Beings in the guild who could've led them this far, but Ainz alone. He and Albedo are given the task to handle the vassalage process of the Baharuth Empire and the Re-Estize Kingdom as well before Ainz returns.
The Craftsman of Dwarf Arc
- Main article: The Craftsman of Dwarf Arc
Demiurge has reported his preparations and activities from the Holy Kingdom to Ainz in full details which Ainz later praise him for accomplishing. Although Demiurge was thankful of the praise, he could not hope to compare his accomplishments to Ainz's, believing that the undead has done much better unlike him. Demiurge recognizes Ainz's feats such as securing a place in the Dwarves’ hearts.
After that topic was done with, Demiurge discuss the vassalization of the Empire is proceeding accordingly while Ainz was gone and they've also drawn up a draft for it. Demiurge questions Ainz on how far into the future have he predicted the course of the Sorcerer Kingdom will move forward from here on out. To his shock, Demiurge is left utterly bewildered by Ainz's answer being "ten thousand years" that he didn't considered it to be of that magnitude so far ahead in the near future. Demiurge told Ainz that a method like utilizing the undead as laborers around must surely be to encourage the other nations to rely on him instead of viewing their troops as dangerous elements.
Awed by Ainz's ambition, he concluded that this must have been the right answer all along for him to look at the world from such a wide angle. Demiurge proceed on to the regards the unknown event will take place during the fall and winter seasons. Despite Ainz's approval, he speculated that the event may not go so smoothly as planned, when there might be some discrepancies along the way. Leaving aside the matter over Empire's vassalization for another time, Demiurge listens to a request from Ainz on wanting a copy of his plan given to him which he accepted.
The Paladin of the Holy Kingdom Arc
- Main article: The Paladin of the Holy Kingdom Arc
Demiurge using his Jaldabaoth persona had enslaved eighteen races of various demi-human tribes of the Abelion Hills and formed a vast coalition aimed at attacking the Roble Holy Kingdom. After stating his intentions at a parley with the human general in command of the Great Wall, Jaldabaoth used his magic to summon a meteor that breached the barrier that protected the kingdom. He ordered his demi-human slaves to begin their attack and for his demons to support them.
At Kalinsha, Demiurge infiltrated the city and began a spree of carnage to attract the attentions of the paladins. When Remedios and Calca assembled before him he noted that none were of strength similar to the warrior he fought in the Re-Estize Kingdom.
- In the Web Novel, Demiurge is the Overseer of the Floor Guardians instead of Albedo, who didn't exist.
- The name "Demiurge" is a being responsible for the creation of the universe. In Platonic philosophy, the Creator of the world. In Gnosticism and other theological systems, a heavenly being, subordinate to the Supreme Being, that is considered to be the controller of the material world and antagonistic to all that is purely spiritual.
- His assumed name "Jaldabaoth" is a supernatural being considered to be a member of the Demiurges. The name Jaldabaoth means "traitor". It seems that Demiurge selected this name as he needed to fight against Momon with the fake identity.
- Demiurge believes that all boys in Nazarick should wear skirts, due to a misunderstanding with Mare.
- Demiurge commands seven custom-made demons. However, he was suppose to originally possess twelve of them. The names of the missing demons stated by Demiurge are Garira, Iabel, Belias, Kainon, and Abiretsia.
- Among all people in Nazarick, Ainz and Albedo are the only person that Demiurge could not read.
- Which domain Demiurge wishes to govern for himself after the world becomes Ainz's, then he will ask for the right to administer the sky on his behalf.
- After Demiurge's debut as Jaldabaoth in Re-Estize, various nations of the New World learned of his existence. However, Demiurge was disappointed that they labeled him as an Archfiend rather than a Demon Emperor.
- (To Momonga): "Both wise in judgments and quick in acting. A flawless being."
- (About world conquest):"If you wish, I will immediately bring the armies of Nazarick and take this jewel box. Presenting this gift to my beloved Momonga-sama, would be Demiurge’s greatest honor.”
- (About human experimentation): "First would be the healing magic experiment. If you cut off an arm and cast healing on the wound, the arm that was cut off would disappear. What happens if you let them eat the arm that was cut off and cast healing, would the nutrition disappear? If we repeat this indefinitely, will the one eating starve to death?"
- (To Albedo about Ainz): "This is still too irrational, naive; a purely emotional judgment. Ainz-sama is the last Supreme Being who remains here. Knowing that he faces a situation where his life may be in peril, it is our responsibility to come up with a plan to remove that danger. Even if we will be blamed afterwards, even if we will have to sacrifice our lives, we ought to step forward and act, right?"