Neuronist's appearance is that of a huge grey bloating corpse with tentacles, heavy makeup and very long fingers with sharp inch-long nails with nail polish. Though its race is androgynous, Neuronist declared itself to be a Big sister. She wears a black leather outfit akin to a Dominatrix
Neuronist is in charge of torturing the prisoners and extracting information from them. She takes delight in her job and inflicting pain on others, especially since her favorite food is brains. She is very talkative, casually conversing with her victims whilst she prepares her tools. She is also quite vain; she considers herself more attractive than both Shalltear and Albedo.
The Undead King Arc
- Main article: The Undead King Arc
The Bloody Valkyrie Arc
- Main article: The Bloody Valkyrie Arc
Shalltear Bloodfallen inquires Solution Epsilon whether or note she got along well with Neuronist Painkill. The battle maid regretfully said that she cannot understand that interrogator’s aesthetic sense. Meanwhile, Albedo informs Ainz Ooal Gown that Neuronist is keeping close watch over the captured Sunlight Scripture members. The Overseer offers a suggestion to Ainz that they should summon Neuronist for guidance in the Frozen Prison, but the latter refuses considering that the interrogator talks too much. After all this is over, Albedo initially plans to lecture Neuronist and caution her not to babble too much as he said until her master said otherwise not to do so.
The Invaders of the Large Tomb Arc
- Main article: The Invaders of the Large Tomb Arc
According to Demiurge, Neuronist Painkill was able to successfully reduce the authority of those in power from the Eight Fingers with the help of Mare and Kyouhukou. With the assistance of these three in their operation, they can now begin to slowly infiltrate their organization's ranks until the Re-Estize Kingdom comes under our full control.
While so, Neuronist was said to have assisted in Entoma Vasilissa Zeta's recovery from her fight with Evileye. When several worker groups invaded the tomb, all of Nazarick was put on high alert to test out its defenses against the invaders. Heavy Masher's group had set off a trap, at least one of its members was sent directly to Neuronist Painkill's torture chamber, where he was repeatedly tortured by her.
The Pleiades Day Arc
- Main article: The Pleiades Day Arc
Neuronist Painkill met CZ2I28 Delta, Yuri Alpha and Aura Bella Fiora in the 6th Floor. She explained that she was going to visit Gashokukochuuou, with the rest of the Five Worst for a house-warming. When she explained the purpose of her gift, a bottle of perfume for men, she offered to educate the young dark elf in being a 'lady'. Though due to her close proximity to Neuronist, she caused Aura to run back to her floor.
- Neuronist Painkill is assisted by a group called the Torturers in her Area.
- Neuronist Painkill has a small torture tool based on the idea of Kidney Stones (which plagued her creator).
- According to Neuronist Painkill, the reason why all the NPCs are completely loyal to Momonga is that because out of the Forty-One Supreme Beings, he continues to stay with them until they were allowed to gain life.
- Neuronist also called as Nurunuru in Vampire Princess of the Lost Country, before residence in Nazarick.
- (To Heavy Masher's Member about his lower body): "My, to think it'd shrink this much. There's no need to be scared."
- (To Heavy Masher's Member): "One of the Forty-One Supreme Beings. He ruled over the other Supreme Beings in the past, and he is very, very cool. If you look at him once, you'll want to swear loyalty with all your heart, too. If Ainz-sama ever calls me over to his bed, I don’t mind offering my first time to him."
- (To Heavy Masher's Member about her master): "There was this one time Ainz-sama was staring at my body. It was the stare of a male selecting a target for his hunt. Then he turned his face away as if he was embarrassed. It made my chest tighten and sent chills down my back."
- (To Heavy Masher's Member): "That's right, a choir. Even fools like you that haven't sworn loyalty to Ainz-sama can dedicate their voices to sing his praises. The goal is a chorus. Ah, how electrifying! It's Neuronist's gospel music dedicated to Ainz-sama."
- (To Heavy Masher's Member about Torturers): "It's no use~. It's not going to break from someone of your strength. They'll cast healing magic over and over, so you can get plenty of opportunity to practice."
- (To Heavy Masher's Member): "Listen well. Because he remained, we, who were created by the Forty-One Supreme Beings, were allowed to exist. Our very existence is to serve him. Do you think we'll show even a shred of mercy to some filthy thieves that tracked mud into the holy place where such an exalted being lives? Do you really think that?"
- (To Heavy Masher's Member): "My creator used to suffer from a little problem called 'kidney stones'. To pay respects to that, we'll start with this. Since it became so small, I don't think we'll have much problem putting it in."
- (To Heavy Masher's Member): "We're going to spend a long, long time together. You shouldn't start crying, because this is only the beginning."