Druella's crest for Demon Realm Lescatie

Demon realms, also translated as monster realms or mamono realms, are areas in the Monster Girl Encyclopedia world which are under the control of monster girls. The monsters' demonic energy warps the environment where they live, producing an ominous ecology of black trees, pink rivers, blood moons, and aphrodisiac-spitting scorpions. Normal lands overrun by monsters can be transfromed into these realms when the demonic energy they release builds to a critical point, causing a metamorphosis within the lifeforms of the ecosystem.

At a more fundamental level than the obvious twisting of flora and fauna, the magical character of the land changes too. Monster girls become even more lewd and ferocious, while human women become rapidly susceptible to spirit energy corrosion.

Book Information

Refer to: Monster Girl Encyclopedia World Guide II; Monster Realm Handbook and Monster Girl Encyclopedia World Guide I; Mana Corrosion and Early settings info; Monster Realm

Demon RealmsEdit

Distorted lands overflowing with the dense magical energy of the succubi and other monsters are called “Demon realms.” The magical energy that fills a demon realm causes that land's earth, water, plants, and even animals to transform. In many monster realms, the scenery is different from that of human realms, and plants and organisms that are unique to the monster realm can be seen.

The scenery of the monster realm, with its ever-somber black earth that is illuminated by plants that glow blue and purple, and works of art that incite lust in humans and monsters and guide them towards sex may appear sinister or obscene to the human eye at times. However, the environment of the monster realm which is even called “a world for monsters” is very comfortable, and an easy place to live for all monsters and the “incubi”, human men who were showered in demonic energy after having sex with monsters and changed into an existence that is more convenient for a monster's husband.

Presently, all of the monsters have become female due to the influence of the “Demon Lord”, a member of the succubus family possessing immense power. I think everyone is well aware of how they changed into having the nature of a succubus and beautiful forms close to that of human women. Because of this, the monsters which used to be fiends who could only perceive humans as prey and feasted on human flesh and blood, have now changed into “monster girls” who perceive human men as life partners, have sex with, and fall in love with them. A demon realm is a convenient environment where monster girls and their incubi partners, lovers, and married couples, can have a more pleasurable, lewd, and happy sex life. Furthermore, the size of a demon realm may vary from small-scale like the size of a village, to large scale, at the state level.

Origins of the Demon RealmsEdit

Aside from the "demon realms" that existed to begin with, there are normal lands that weren't demon realms where humans live (noted as “human realms” from now on) that transformed into demon realms due to various factors. The main causes of human realms changing into demon realms are as follows: a national policy of co-existence with monsters, an influx of monsters due to a monster invasion, or an increase in monsters due to the monsterisation of human women. Due to those reasons, the land becomes filled with demonic energy. Monsters naturally release slight amounts of demonic energy from their bodies, and monsters with husbands will additionally release plenty of dense demonic energy.

If there's only one or two monsters, a tiny amount of demonic energy is no big deal, but when many monsters gather together in the same place, such as in towns, etc and the monsters do nothing but have sex with their beloved husbands all the time, both the amount and quality of the magical energy released swells up in proportion. And then the vast amounts of dense demonic energy causes various things in a human realm to transform, then it changes into a demon realm, a world where monsters can get off making love with their husbands.

Additionally, there is a monster race that can single-handedly release enough magical energy to change a human realm into a demon realm as long as they obtain a husband, Dark Matter, which is also the author's race and the demon princesses which lead the monsters and have the power to change human women into whatever kind of monster they please, the Lilim sometimes invade human realms on their own, etc. so sometimes demon realms are even born from just a single monster. Other than that, in some cases, the “four great elementals” that comprise nature itself such as earth, water, etc. change into monsters, and when they gain power by having sex with human men and transform into “dark elementals”, the earth or water, etc. changes into that of the demon realm faster than the rest of the land, and from there, the entire land gets converted into a demon realm.

Furthermore, once the signs of conversion into a demon realm begin to appear, there's pretty much no stopping the conversion. The magical energy released by monsters that fills the air changes human women into monsters, and women who become monsters release even more energy. Before long, the air becomes teeming with demonic energy and it seeps into the earth, water, etc. Fruits and vegetables that grow with the benefit of demonic energy-enriched earth and water, suck up magical energy from the earth, water, etc and store it. Demon realm crops will also appear And from all that, human women will change into monsters. Once the signs of conversion appear, the process of the conversion of the land into a demon realm rapidly speeds up due to a chain reaction of such violations of demonic energy.

Naturally, conversion is an extremely joyous phenomenon to monsters and incubi. Especially monsters, since conversion is connected with having a fulfilling sex life with their husbands, many monsters can sensitively feel the signs of change, and their bosoms swell with anticipation at the prospect of the days full of pleasure and love that are to come. It's joyous to incubi in the same way, but unlike monsters, except for some who are adept at handling magical energy, the signs are difficult for them to notice. Especially in the case of a gradual conversion, the first slight signs might just feel like: “Lately my bride has become cuter (more beautiful).” “Lately my body feels better. It's good feeling at night too.” It seems many of them become aware of it when the scenery around them first starts changing into that of a demon realm.

I'll describe it in detail later in another section, but during conversion, due to the influence of pervasive demonic energy, human women change into monsters and human men change into incubi. During transformation, people sometimes temporarily feel like they're going mad, but up until now, negative health benefits, or bad influence to the human body and mind due to conversion haven't been confirmed. On the contrary, demonic energy is a vital energy that raises the longevity of living things just like the “spirit energy” that humans posses. Since the earth is filled with that vital energy during conversion, it actually makes the human body rather more durable and healthier. The changes in the body due to becoming a monster or an incubus along with the amplification of one's life force often cures the illnesses that people had when they were human.

Note from the Wandering Monster Scholar: Concerning bad influence to the human body, some would say monsterisation is just that. Period. But from a monster’s point of view, it's not a bad thing. Pardon me.

Environment of the Demon RealmsEdit

Atmosphere of the Demon RealmEdit

Monsters naturally release a slight amount of magical energy from their body. They will release a greater amount of higher density magical energy after having sex with their husband. For this reason, the atmosphere of the demon realm is always full of fresh demonic energy.

The layer of high-density demonic energy in the atmosphere of the demon realm blocks out sunlight and causes it to be dark during the day and at night, the moon seen through this layer of energy appears crimson and illuminates the demon realm. The magical energy in the air has the property of glowing when illuminated by the crimson moon, and at night, surreal demonic light like that of a bright firefly hangs in the air. The towns of the demon realm illuminated by this surreal demonic light never sleep, just like an entertainment district. In the demon realm, it's brighter at night than it is during the day. Furthermore, the plants and animals of the demon realm, including monsters and incubi, can live without sunlight, so it's not harmful to them in any way.

The air of the demon realm, filled with thick demonic energy, feels different to humans and monsters (including incubi) and affects their bodies in completely different ways. For humans, the thick magical energy in the demon realm's air is a bit too much. The air of the demon realm probably feels stagnant and heavy. The air that enters the human body through respiration is saccharine, and it gradually robs people of their reason and ability to think. Eventually, the head gets fuzzy, and the body flushes feverishly. Meanwhile, they become elated and experience arousal before ultimately going mad with lust. Human women who have gone through it are already like half-monsters psychologically, and their mind is full of obscene desires. In this state, they will either gradually change into “succubi” and assault human men, or give in to their burning desire and hotly flushing body, and assault and have sex with human men, in which case they will suddenly change into “succubi” because of the human spirit energy obtained. And then, after being assaulted by women such as them and other monsters who lived in the demon realm to begin with and absorbing lots of demonic energy, men will lose the will to resist. Not only that, in some cases, men will have sex with them of their own free will and change into incubi.

In the case of monsters, it's just the opposite. The air of the demon realm feels fresh and refreshing. The sensation is very similar to the way humans that live in towns sense the air of the countryside and forest, etc. The air is filled with demonic energy, which is a vital energy. It activates the body of monsters who inhale it. Monsters become more uninhibited when it comes to sex and pleasure because of this, and they'll end up trying to aggressively assault and mate with men. ( In the case of incubi, it activates their body in the same way, increasing desire for their monster wife). For humans, the air is like an aphrodisiac, but for monsters, it's something that makes them more sexually aggressive, yet doesn't “drive them mad”. That's not to say that it doesn't have an aphrodisiac effect on monsters. It's just that monsters are always full of sexual desire and always want their husband. Their ordinary life is full of sex and pleasure, so an aphrodisiac effect to this degree doesn't even register to them, so they don't go crazy and lose the ability to think at all. For this reason, even living in the demon realm, they are still able to do other life activities besides sex and they can work. It's also possible to endeavor in studies and research, like the author.

Note from the Wandering Monster Scholar: Even without the demon realm air, it's like the monsters just always lust for their husband. Also, even if the air of the demon realm doesn't drive them mad, the scent of their husband's spirit energy in the air does drive many of the monsters mad.

When a human woman showered in demonic energy changes into a monster, in most cases, she changes into the same kind of monster as the owner of that magical energy. Although we refer to it indiscriminately as “demonic energy”, to be more precise, the energy possessed by werewolf monsters is “werewolf demonic energy”. The energy possessed by “slime” monsters is “slime demonic energy”. For example, a human woman who received werewolf demonic energy in her body would transform into a werewolf. However, monsterisation caused by the above-written-air, generally causes human women to change into “succubi”. This is because various races are residents of the demon realm and the demonic energy in the air is also a mix of many different magical energies. Currently every race of monsters is under the influence of the Demon Lord, who is a “succubus”. They are connected with the Demon Lord through magical energy and they have a portion of the Demon lord's demonic energy inside of their body. For that reason, all demonic energy also includes “succubus demonic energy” and there is also plenty of succubus demonic energy floating in the air. Perhaps because they're related to the current Demon Lord, succubus demonic energy is even more powerful than other demonic energy. When magical energy leaves the bodies of two different races of monsters and mixes together, the succubus demonic energy contained in both wins. There is a law that all other magical energy is taken in and converted into succubus demonic energy. For this reason, monsterisation caused by breathing the air of the demon realm generally results in a “succubus”.

However, although it is extremely rare, there is an exception in the case of demon realms that are inclined towards just one race. For example, in a demon realm inhabited by only werewolves, the magical energy in the air would predominantly contain werewolf demonic energy and it would win over the succubus demonic energy, therefore women monsterised by the air of this realm would end up changing into werewolves.

Water of the Monster RealmEdit

Just like in the human world, the demon realm's water is necessary for most life. It is clear and transparent just like the water of the human world, however in areas with high concentrations of monster magical energy, it can appear to have a pinkish tinge. Also, it's a bit thicker than the water of the human world.

Demonic energy is abundant in the demon realm's water. As was the case with air, when humans and monsters absorb the water, the effects are vastly different. To humans, the water feels like a liquid that's thick and syrupy like honey. As was the case with the air, there is a gradual aphrodisiac effect, but compared to the air which causes the body to flush, this works from inside the body, or rather, the body's core. Especially in human women, it causes the womb to become very hot and throb, seeking a man. Additionally, it causes reason and the capacity for normal though to be melted away by demonic energy even more so than in the case of the air. Thoughts will become syrupy with lust like the demon realm's water. And then eventually, they will change into succubi adapted for the demon realm.

In contrast, to monsters, the water has a bit of thickness, but it feels fresh, the feeling when it goes down the throat is nice, and it's just barely sweet. Furthermore, monsters who drink it feel like the inside of their body is refreshed as well as their throat. Whether in the human world or the demon realm, there is magical energy released by humans and monsters floating in the air. Monsters can get a slight amount of it just by breathing it in and absorbing it in their body. It's because the demon realm's water has the effect of aiding in melting down and absorbing extraneous demonic energy that was taken into the body but still hasn't been absorbed by their own magical energy. In this way, scraps of magical energy are washed from the body, resulting in a refreshing feeling.

Plus, this is what's vital to the monsters. If they wash away all excess magical energy before absorbing human spirit energy, then that excess won't interfere and they can fill their body with only the magical energy of their beloved husband. Many monsters always use this water to purify the inside of their body before using their mouth to get their husband's semen.

The pink water of lakes where “undine” who changed into dark elementals live has a particularly potent effect, and it makes their husband's magical energy which already tastes good to begin with become mind-blowingly good. It's popular with most monsters, and is distributed as “Undine Spring Water” not only within the demon realm, but outside of it as well.

Earth of the Monster RealmEdit

The Demon realm's earth and soil stores magical energy that pours down from the demon realm's air and magical energy carried by the demon realm's water, so it is extremely rich in demonic energy. Out of all the elements of nature, it stores the highest concentration of demonic energy. This is one of the things that really infuriates me, but according to the scholar of monsters, the anti-monster organization, “the order of the chief god” and some humans that have been spreading rumours, or acknowledging the idea that the demon realms are barren lands and that they have desolate wastelands, poisonous swamps, etc, but they're mistaken and it's totally wrong. The demon realm's earth is rich in magical energy, in other words, nutrients. Plants and crops peculiar to the demon realm grow and bear great fruits for all the living things of the demon realm. In the land of the demon realm covered in demonic black soil, there are trees that are different from those of human realm. They are black with crooked shapes, having green and blue leaves that shine in the moonlight, bright shining flowers that bloom in profusion, and bright colored, colorful fruit. It's a place overflowing with the rich fruits of life and nature, even more so than the human world.

Additionally, the scenery described above often looks ominously eerie to humans, but the sense of monsters and incubi is different from that of humans, and it feels extremely beautiful to them.

The demon realm's soil which contains an abundance of magical energy is best suited for the plants of the demon realm which rely on demonic energy as a nutrient for growth. There is plenty of magical energy in the soil and the more rich it is, the better the crops of the demon realm grow. Plant type monsters such as “alraune (encyclopaedia I – p.34)” and “mandragora (encyclopaedia I – p.36) “ also grow into stronger, more lascivious individuals. In order to enrich the soil, it's important for the demon realm to increase the demonic energy present, raising its quality and density. In other words, monster married couples and lovers who live in the demon realm must have more sex so that the monsters can release larger amounts of more potent demonic energy, being deeply in love is the most important thing to make the demon realm's earth richer.

Varieties of the Monster RealmEdit

Monster realm is a “general term” for special lands that changed to be convenient for monsters to inhabit. Many humans and monsters just use the term “monster realm” without making any minute distinctions. Only a fraction of scholars and intellectuals use the official classifications that have been distinguished, but actually, monster realms can be divided into several varieties.

Dark Monster RealmEdit

These are orthodox and generally well-known. It's always dark during the day, and the red moon rises at night. The land is coloured with black soil, and ominous blue and purple plants, etc. It's the most common type of demon realm out of all of them. A demon realm becoming of a demon realm.

The term “demon realm” often indicates this type of demon realm. The scenery that has been described in the items of this book up to this point, and that which will be introduced in items after this is mainly that of the “dark demon realm”. The demon realms that originally existed were almost entirely of this type. Most of the demon realms that are distorted human lands are also this kind of demon realm.

When there is a monster invasion, or a huge influx of monsters all at once in a land previously uninhabited by monsters, in the case of sudden geographic transformation brought on by the previously mentioned “dark matter”, etc. or in the case that the majority of the monster inhabitants are demon or undead type, most of these lands will become dark demon realms. Compared to the “light green demon realm” to be introduced in the following item, the concentration of demonic energy is extremely high, so demon realm crops are rich in variety and easy to grow and monsters can just spend their days in depravity with their beloved husband. The magical energy released from that, is absorbed causing the crops to grow rapidly. Also, animals and ore peculiar to the demon realm that are highly sought after among monsters are produced. However, one hardly ever sees the normal fruits and vegetables that are found in the human world. Even if one tries to grow them, they mostly distort into the crops of the demon realm. There is a highly condensed magical energy in the air and water, etc. It's the best environment for spending one's days having sex with her husband, so it's ideal to monsters. If one wants to lead a more obscene, pleasurable, hedonistic lifestyle, this kind of demon realm is recommended.

Bright Green Monster RealmEdit

These only started to spring forth in recent years, but they are a peculiar kind of demon realm that are increasing at a staggering rate. Unlike “dark demon realms”, the sky is bright blue during the day, and the brilliant light of the sun illuminates the earth. The ashen earth that receives sunlight is covered with green plants. Demon realms that have scenery which is hardly different from that of the human world in this way are called “bright green demon realms”. In the case of monster friendly states which co-exist with monsters, and some parts of the Zipangu region, etc. that gradually change into demon realms, or in the case of demon realms where the monster inhabitants are mostly races originating in nature such as beast man type or plant type, it seems to be easier for them to become one of these bright green demon realms.

Even though they're all beastman type, in the case where there are many Holstaur and Weresheep, etc., it will be easy for the land to become a bright green demon realm, but lands under the rule of races that prefer a hedonistic lifestyle such as Youko will generally become dark demon realms, etc., so we can't say this as a rule.

Compared to dark demon realms, the demonic energy in the air is somewhat thinner and it's just a bit more difficult to grow demon realm produce, but most normal crops that existed in the human world to begin with can grow without being distorted by demonic energy, so demon realm crops and human world crops are in a state of coexistence. Additionally, the soil of the demon realm contains more nutrients compared to that of the human world, so even human world crops are extremely easy to grow. However, on the other hand, animals and ores peculiar to the demon realm can hardly ever be spotted.

Most of the bright green demon realms have an idyllic, quiet atmosphere. This kind of demon realm is recommended for couples that want to take it slow while living in harmony and having sex.

Yet, only monsters and incubi can take it easy in these realms, not humans. Even though these bright green demon realms almost look the same as the human world, they are demon realms through and through on the inside. I previously mentioned that the demonic energy in the air was a bit thin, but that's only in contrast with the dark demon realm. Just like that of the dark demon realm, the air and water drives humans mad with lust. The demonic energy is more than thick enough to gradually convert humans into monsters and incubi.

Other than those with a lot of magical energy such as sorcerers, etc, the average human can't tell these demon realms apart from the human world at a glance. There are even tales of those who don't realise that they themselves have become incubi while living among the incubi residents who look in no way abnormal. For that reason, it seems that a lot of humans from the order of the chief god enter these demon realms without realising it and easily change into incubi and monsters.

Furthermore, there are a few differences from the human realm other than the fact that demon realm crops are produced. As in dark demon realms, when night falls, the magical energy in the air illuminated by the moonlight glows, dancing fantastically in mid-air. This beautiful light is fainter and weaker compared to that of the dark demon realms, so it looks just like real fireflies, including the way that it floats.

Spirit RealmEdit

The realms known as “spirit realms” are peculiar even amongst the demon realms. As the name suggests, they are demon realms that exist in another dimension. Most of them were created in new dimensions by gods or monsters with vast power rivalling that of a god. The holy land of the fallen angels that was created by the fallen god, “pandemonium”, and the “mysterious kingdom” full of mystery and pleasure created by a certain lilim, etc. are all categorized as “spirit realms”. Since they aren't connected by land, it's normally impossible to enter or leave one of these realms by walking. The method of entry varies depending on each individual spirit realm, but peculiar spells, rituals, portals (teleportation spells), or the assistance of a specific race are necessary.

It's normal to love one's own husband more than anything, and to prefer to have sex with one's husband, but many of the monsters of the spirit realms have peculiar culture, ideology, and values that are different from that of normal monsters, and the scenery and nature of these demon realms is also vastly different from that of the above mentioned dark demon realm and light green demon realm. There is also peculiar produce that can only be found in these demon realms. You would think that these places would be cut off from the outside world, but there is a surprising amount of travel back and forth and intermingling with other demon realms. There is active cultural exchange and exportation and importation of products, and I hear that many monsters travel to these sort of spirit realms on their honeymoon.

Note from the Wandering Monster Scholar: Many couples who like a spirit realm (especially the sex that happens in the spirit realm) remain permanent residents. Also, I hear that there is a branch of Sabbath in most spirit realms.

Royal Demon RealmEdit

Main article: Royal Makai

An immense demon realm that can even be said to be the main stronghold of the monsters. The demon lord's citadel, “demon lord's castle” is located there. In its centre there is a city cantered around the enormous Demon Lord's castle which is more enormous than any other city in all the human world and demon realms. Technically it's classified as one of the dark demon realms. The scenery is also mostly the same, but perhaps because of the monster lord's presence, the magical energy is so highly condensed that a normal dark demon realm doesn't even compare. It goes without saying that ordinary humans cannot resist monstarisation, but not even veteran heroes can. The monsters that dwell in this demon realm filled with the greatest concentration of demonic energy, grow even more powerful and lustful than the monsters of other demon realms which are in turn more powerful than the monsters in the human world, plus, as previously mentioned, the air has the greatest concentration of demonic energy, so humans who enter this demon realm are definitely not coming back out as humans.

The royal demon realm is also called “deepest part of the demon realm”, but there is much intermingling with other demon realms, and monster-friendly states, etc. that is, all countries except the anti-monster states under the control of the order's forces. There are various amusement facilities such as an enormous art gallery, a colosseum, etc. and the magical research institute which is owned by Sabbath.

There are also overwhelmingly huge shopping districts, etc. that can't all be seen during a single stay, so there are lots of visitors from outside. The Demon Lord also seems to value cultural exchange with every demon realm, every nation, and every region. While the order's soldiers desperately march on, portals (teleportation spells) are periodically being set up that connect to each demon realm and monster-friendly state.

I recommend living there permanently, but even if that's not your intent, I recommend that you at least go there once with your husband and see it.

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