Demon World

''This article is about the Manga version of the Demon World. For alternate pages referred to by this name, please click any of the icons above.''

The Demon World is the main setting of The Promised Neverland. The Demon World is part of the world that many years ago, was split into two between humans and demons after The Promise was signed with the Ratri family. The part of the world belonging to the demons is comprised of many bizarre ecosystems and creatures, some of which include feral/bestial demons.

History
Millennia ago, before the construction of plantations, both demons and humans shared the same world, which led to frequent hunting of humans by the demons. Some humans soon after did the same, while the rest worshipped them out of fear of getting eaten. This became a continuous cycle as both sides killed and feared one another. After countless violent wars and massacres, a clan of humans called the Ratri family stood up to the demons and made a treaty known as The Promise.

Bayon's Proposal
Bayon and the government of demons held a meeting, discussing how they should consume orphans when they are forbidden to do so after the Ratri Clan's proposal of a treaty. Bayon came out with the solution of building the farms to "cultivate" the young of the humans so as to satisfy the demons' need of consuming human flesh, as well as to comply with The Promise. Therefore, Bayon's solution was accepted and included as part of the treaty.

The humans gave some of their children to the demons as a parting gift when they fled from the Demon World. The children were later kept in "plantations" (institutions that take care of the children) as livestock for the demons to consume.

The Signing of the Treaty – The Promise
We shall make a treaty as follows: "Human beings shan't hunt 'demons' anymore. In return, 'demons' shan't hunt humans either. This world we live in shall be divided between both.".

A proposal —otherwise known as The Promise— was formed by the first head of the Ratri family. It declared that "humans and demons are restricted from further hunting." Afterwards, the world was broken into two — one side belonging to the demons while the other belonging to the humans.

Birth of a Religion: Heathen
Some demons did not approve of this deal and thus refused to even nibble any of the children born in the farms. This caused these demons to be branded as "heathens" and were shunned for their behavior. However, while their religion prohibits them from eating humans born in the farms, they wait for The Promise to be broken and be able to hunt humans again.

Bloodsucker Trees
Bloodsucker trees are found in the demon forests. They are unusual because they feed on living organisms, such as animals and humans. In the Bloodsucker Trees Area, sentient vines drop creatures beneath the surface and suck the nutrients out of them.

The trees are thought to be the Snakes of Alvar Pena, as mentioned in the Adventures of Ugo.

These trees die, which Sonju make a tunnel by connecting the Bloodsucker Trees underground forming a maze that he says only him and Mujika can find the exit. But later Mujika says she would be lost.

Anemone Plants
The Anemone plant is a large, bulbous plant that, when broken open, contains fresh, drinkable water. Its species name is unknown, but as their Adventures of Ugo counterpart is described as an anemone, they are often referred to as such.

Jewel Flowers
Described as jewels in the Adventures of Ugo, these flowers give off a beautiful glow admired by the children. They are often seen used in demons' lanterns, and grow rather plentifully throughout the demon world. In some colored art, the flowers' glow is depicted as being of a light blue color.

Monkeys
Monkeys are found in a forest encountered by the B06-32 refugees on their way away from the blown-up shelter. Their appearance most closely resembles real-life Squirrel Monkeys, though their exact species is currently unknown.

Crawling Fish
Crawling fish-like creatures are seen in the caverns beneath the Bloodsucker Trees.

Horses
Numerous horses are seen throughout the series, generally used by humans in the demon world.

Flying Newts
Newt-shaped creatures with insectoid wings are frequently seen flying around in various parts of the demon world.

Large Insect
A swarm of unspecified large horned insects appears in caverns beneath the Bloodsucker Trees.

Candle Trees
In the Search For Minerva Arc, Mister leads Emma and Ray through a forest of these trees. They are described as feeling as though they are made of stone and looking like melting candles. Various vines and lichens grow on them.

Sleipnir
The demonic variant of horses, most notably ridden by Mujika and Sonju, but also being used by other demons. This creature has a scaly texture, a long, thick tail, three pairs of limbs (one back pair, two front pairs), a short mane, and a pterodactyl-like head.

Demon Forest
A vast area of dense trees and wildlife located outside the human plantations, it contains a variety of bizarre fauna and plants.

Heathens Hideout
The demon Sonju created a path comprised of dead Bloodsucker Trees in order to serve as a hideout for himself and his companion Mujika. This is to avoid the plantation demons who reject them as "heathens" for not eating humans. However, it is later revealed that the heathens aren't forbidden from eating humans, but are forbidden from eating any humans that are born in the farms. As such, they wait for the day that humans born in the wild will come to pass so they can hunt again.

Grace Field House
One of four farms where the human children left behind by their ancestors are raised as livestock. Grace Field is the top Premium Farm with the hardest tests and the youngest maximum shipment age. It is also the smallest Premium Farm, being made up of a single building of each plantation. The children and are branded with identifying tattoos on their necks made up of 5 numbers and are shipped out between the ages 6 and 12 to become offerings to an unknown demon lord. It consists of five plantation and a headquarters. Plant 3 was burnt down when 15 children between the ages of 5 and 11 escaped. Afterwards, the children under five were divided up and sent to one of the other four plants.

Glory Bell
One of four farms where the human children left behind by their ancestors are raised as livestock. The inside of Glory Bell is unknown, but it is known that there is a large bell on the property. The children and are branded with identifying tattoos on their lower abdomen made up of letters and numbers. Unlike Grace Field, the maximum shipment age at Glory Bell is 15. A group of 19 kids escaped from Glory Bell and were journeying to Minerva's second shelter at Goldy Pond before they were captured by Poachers and all killed, with the exception of Mister and Lucas.

Grand Valley
One of four farms where the human children left behind by their ancestors are raised as livestock. Grand Valley appears to be very large and has multiple buildings placed in a town-like formation. The children and are branded with identifying tattoos on their upper chest made up of Roman numerals, followed by a 3-number sequence, a dash, and 3 more numbers. The maximum shipment age at Grand Valley is 17 years old. In this farm, children are being prepared to be shipped out to Goldy Pond because Grand Duke Leuvis serves as a purveyor so he has a lot of power both in Goldy Pond and Grand Valley. All members of the Goldy Pond Resistance movement and the likes of Theo, Monica, Jake, Mary, Lucy, Malcolm, Fred, Elliot, Michael, and Johnny came from this orphanage.

Goodwill Ridge
One of four farms where the human children left behind by their ancestors are raised as livestock. Goodwill Ridge appears to be very large and has multiple buildings placed in a town-like formation. Of all of the Premium Farms, the littlest is known about Goodwill Ridge. It is unknown what the identifying tattoos the children are branded with look like or what part of the body they are on. It is also unknown what the shipment age for Goodwill Ridge is. The only known children to come from this farm are Cislo and Barbara.

Factory Farms
Factory Farms are hundreds of farms that contain cheap meat for the demon population. The children in these farms have no free will of their own or any power of speech, as they are only kept barely alive and spend all of their lives being fattened up by the demons to be eaten by them. One of the children living in Goldy Pond, Adam, came from a Factory Farm. Two kids in Norman's group, Hayato and Jin, also came from a Factory Farm.

Shelter B06-32
Shelter B06-32 was Minerva's first hideout and was set up as both an armory, a source of knowledge about the world's affairs, and a safe haven for escapees who possessed promised pens and were smart enough to escape the plantations.

Goldy Pond
While Shelter B06-32 was only a temporary hideout for escapees to meet with Minerva and regroup, Goldy Pond was his actual base of operations. It contained a small village that served as a front for the true entrance, hidden under a silo and several ladders underground lies a floating island, which contains an elevator to the human world when a promised pen is inserted into it.

Cuvitidala
The ancient ruins of Cuvitidala are the central focus and namesake of the Cuvitidala Arc. It is implied that the place was once a sacred shrine, but its use has been long since discontinued. As it has been closed down, only Emma, having the eye amulet, can use the shrine's clairvoyant abilities.

Trivia

 * The demon world is theoretically divided into four areas, as per Minerva's pen, with Grace Field House as the origin point. Going clockwise, they are labeled A, B, C, and D.
 * The design for the forest in the Demon World was modeled after the nature in Yakushima.