Inferia is a place with plains full of grass and sunny weather. The Greater Craymels from this world are Efreet, Sylph and Undine, and the world's unifying Craymel is Rem. The Craymels are considered to be spiritual entities who demand the greatest respect, and Craymel Mages are the mediums between the Craymels and the physical world. All high-level Craymel Mages are given an "Orz Earring" to facilitate a means of understanding Craymels, though most never come in contact with the Greater Craymels themselves. Inferia is organized into a global empire, the Inferia Empire (インフェリア王国 Inferia-oukoku?), ruled over by its king from the capital, Inferia City. The social structure is very rigid; the higher classes, especially the royal family, are believed to be fundamentally different from the common people, and the king is considered to be a ruler by divine right. There is a large and vocal religious presence, the Church of Seyfert (セイファート教 Seifaato-kyou?), who worship Seyfert as the god of creation. There is actually debate among commoners as to who is truly superior, Seyfert or the king himself. Nevertheless, the world has been at peace for at least 18 years due to the strength of the king's leadership, and none question his authority under penalty of death.
While the level of technology in the world is still in the middle ages, great advancements in science have been established, though all findings by the academic community must still be altered to satisfy the word of the king and Church of Seyfert. Any findings that are contrary to the king's word or the teachings of the Church are automatically declared to be blasphemous, and the spreading of such perceived misinformation is considered to be a crime of sedition that would destabilize the peace of the empire. This has inhibited technological growth greatly, and, combined with the absence of wars, there has been no motivation to enhance the present state of technology. Due to the presence of vibrant sunlight, heat, and water through the appropriate Craymels, farming is a highly significant industry in many areas.
The people of this world are known as Inferians (インフェリア人 Inferia-jin?), who view themselves as the recipients of Seyfert's blessings. Any natural disasters or even inconvenient situations are blamed on the people of Celestia, believing that the Celestians are directly interfering with their world to cause trouble. However, this idea actually contradicts the Inferians' belief that their world is at the peak of progress, as well as that the barbarian Celestians could not possibly be capable of anything the Inferians could not achieve. This contradiction, however, is merely hand-waved as the king's word. All Inferians have light-colored skin in spite of the presence of direct sunlight due to Light-elemental Craymels. While they have their own language, the Inferians use Melnics to communicate with Craymels and perform invocations. While there are some books that teach basic Melnics in various libraries, none in Inferia can claim to understand the spoken language as a means of conversation. In Celestia, Inferia is referred to as "FUEDI", meaning "Far", and its people are known as "FUEDIUEMUSU", meaning "Farians".
Inferia has been peaceful for a long time, but this is due to the strict nature of the government and its religious institutions. During their travels, Reid Hershel and his companions are, at one point, sentenced to death for sedition. Although they did not attempt to rebel against the king, their search for someone who might believe Keele's findings about the Seyfert Ring is seen to be insurrectionist in nature.
- Inferia derives from infernus, which is Latin for "hell".
- The official fruit of Inferia is kirima.
- In Tales of Puppet, Reid explains that the Inferians wear chokers that vary in material depending on their rank. The material used in each rank goes as follows; Gold is reserved for royalty, silver goes to the nobility, and bronze is for the average soldier. Each of the commoners' chokers vary in material and color depending on gender and profession. The men's are made of wood, as opposed to the women's whose are cloth. The scholar's choker is colored white, the merchant's is green, the hunter's is brown, and the farmer's is red.