Powerful human sorceresses who changed into undead. There are also those who chose to become liches of their own accord in pursuit of eternal life and limitless knowledge. They possess much greater magic than they did while amongst the living. They are terrifying high rank undead that can freely use various spells such as “necromancy” which reanimates corpses into undead servants, and “eromancy” which manipulates lust and heightens pleasure. Most of them have a strong fixation with and thirst for knowledge of sorcery, and the pleasure of sex, which they awakened to after becoming monsters. Even in death, they continue their lewd magical research and experiments to master sorcery and reach the depths of pleasure.
They usually immerse themselves in their research at dwellings away from human settlements, and they rarely reveal themselves in front of people. However, a human man is absolutely necessary to them as they replenish their magic power by taking in spirit energy, a man’s body serves as a test subject, and there are spells and sexual experiments which require both a man and a woman to perform, so if they spot a man, they’ll aggressively attack in an attempt to subdue him.
To them, even their own body is a material for experimentation, and it is imbued with various lewd spells so that they can maximize the pleasure for themselves and their partner during sex. When they attack a man, they also imbue the man’s body with various spells. By having sex when each other’s bodies are imbued with these spells, they enthrall a man with their sorcery and body.
Most of them don’t take much interest in others, with the exception of the man they choose as their husband, a monster’s one and only partner who shares the greatest pleasures with her. They have an even stronger attachment to him than to sorcery.
The man who became their husband will spend his days thinking and pursuing experiments of sex and magic in order to reach the depths of pleasure and sorcery as their eternal partner.
Their body is imbued with various spells by their own hand to become more lascivious, sensitive, and insatiably lustful so that they can obtain more spirit energy and pleasure. Once they have sex with a man with their body in such a state, they will be attacked by so much pleasure that it would normally cause them to lose their mind and become a beast. However, while they do immensely enjoy the deep pleasure, they maintain enough composure to analyze sex, pleasure, and the effects of the spells they used. This is because they put their soul into a vessel called a “phylactery,” and they distance their soul from the pleasure and spirit energy their body receives.
Due to this, they can enjoy pleasure and maintain the capability for calm, objective thought even right in the middle of sex with their husband whereas other monsters’ minds would be consumed by pleasure. But if the phylactery is damaged, the soul returns to their body. If they have sex in that state, not only their body, but even their soul will be swallowed by pleasure and spirit energy, and then they’ll become unable to think about anything but their beloved husband in front of them.
Currently recruiting a test subject! It's an indecent workplace where the orgasmic expression never ceases!
This time's update is the "lich", a high rank undead sorceress with mastery over various spells. They're highly inquisitive sorceresses who became undead to master sex and sorcery. In order to reach the depths of pleasure, they direct all their thirst for knowledge, curiosity and ambitions towards sex. They even use their own body as a guinea pig, altering it into an erotic body imbued with sorcery. They're currently recruiting a male test subject (husband) who will cooperate with (sexual) human body experiments.
As always, please check the monster girl encyclopedia profile for details. 
- Lich is a type of undead creature in fantasy fiction.
- A lich can make a new phylactery if the old one breaks.