Pandemonium is the heaven of the Fallen God. The lair of dark angels and dark valkyries, it is a spirit realm dimension of the Monster Girl Encyclopedia world where time flows strangely. Although most monster girls would spend all day raping men if they could, in Pandemonium the power of the Fallen God suspends the normal rules of exhaustion and appetite so that this is literally what happens.
Exactly how the passage of time is altered in Pandemonium isn't clear; "space-time is warped by the power of the fallen god, and the same moment continues on forever", but the growth and harvesting of Corruption Fruit implies that there may be some sort of progression from one moment to the next.
The general information on spirit realms suggests that, despite Pandemonium being a different dimension, travel and trade with the regular world is probably common. Dark priests who have finished their missionary positions (hurr) in the human realms retire to Pandemonium with their husbands, but the realm may also serve as a destination for other monsters' honeymoons, and the ubiquitous Sabbath is likely to maintain a branch there.
A palace where “the fallen god” rules that is said to exist in a different dimension than the human world. In the same way as the palaces of other gods, it is comprised of the fallen god's palace, and a castle town where her servants the lesser divinities reside. Fallen angels such as “Dark Angel” ect. live here. In Pandemonium, space-time is warped by the power of the fallen god, and the same moment continues on forever. In this place, there is no starving or growing old. The only thing that dark angels do once they've brought back the human man they like is to keep having sex with the man. In this place, no one ever runs out of stamina or gets tired out. It is said that the men and dark angels just keep doing nothing but have sex. As they can't fully sate their lust here, their desire to continue to drown in pleasure never ends.
It is said that they dwell in a place called “Pandemonium.” Once she has completely corrupted a man she has captured, a dark angel will carry him off to this place. It is said to be a location where space-time is distorted due to the power of the “The Fallen God,” a dimension where there's no aging or starvation and the same moment continues for eternity. After returning to this place with a man, a dark angel will have sex with the man for eternity in the absence of time, leading a lifestyle that is solely consumed by the desire to continually indulge in pleasure.
The realms known as “spirit realms” are peculiar even amongst the monster realms. As the name suggests, they are monster realms that exist in another dimension. Most of them were created in new dimensions by gods or monsters with vast power rivaling 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 monster realms is also vastly different from that of the above mentioned dark monster realm and light green monster realm. There is also peculiar produce that can only be found in these monster 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 monster 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.
Eventually the monsters devotees of the Fallen God who obtain a human man head for their utopia, the Fallen God's holy land and castle, “Pandemonium”. Due to the power of the Fallen God, time is distorted in that land. It is said to be a space where the same moment continues eternally and there's no aging or growing hungry. There they are promised days of having sex with men forever consumed by unfathomably deep desire, and a bottomless fall with continuous indulgence in pleasure.