The Place where Demons dwell does not have a particular name. It Is just called Demon world. They have Various cities and landscapes and it is not what you would think. They have Four major Kingdoms.
The Air kingdom and its capital city of Shangri La it is nestled in the valley deep in the mountains. It’s queen is Tamamo-no-Mae, A void kitsune, while her power is of destruction and Chaos her reign has been a peaceful and prosperous one. She is said to be a kind ruler. Her younger brother Ace , an ocean kitsune, is the heir to her throne. Her Consort is Namahage also known as the Boogeyman. He was one of the creators of the ancient curse.
The Fire Kingdom and its capital city of Heliopolis is in the middle of a vast desert. It is also ruled by a queen who is very different from her Airy counterpart. The Queen of this Kingdom is the Egyptian Lion Goddess Sekhmet. She rules with an iron fist and a temper hotter than the sun that rises and sets on her kingdom. Her heirs were her two sons Evan and James. Through undisclosed circumstances they are now deceased and the title of heir goes on the their children. Raven, Bob,Jesse, Leon, and Cecil. She claims no Consort.
The Water kingdom and its capital City of Atlantis is for the most part under the water. A small portion of the palace has been left above the water for visiting dignitaries and diplomats. They also have various island towns for those who wish to live a water kingdom life but is unable to live water. The King of Atlantis Is Poseidon the Greek God of the Ocean. His heir is his son Triton. His Wife is Amphitrite.
The Earth kingdom and its capital city of Lemuria. It is located in a dense forest and most of its building are located in the treetops. Xbalanque, the Mayan jaguar sun god, is the benevolent king of this lush and green kingdom. The trees are plentiful with fruits and wildlife. Some towns are in the treetops like the capital others are on the ground. Either way it is easy enough to get lost without a guide unless you know where you are going but that can be said for all the kingdoms. His Heir was his daughter Ix Chel. With unforeseen circumstances she too has been lost to time much like Evan and James. His current heir is Tiamet, a trusted Jaguar Demon and once was a friend to his beloved daughter. His wife is Awillix, the Mayan Jaguar goddess of the moon.
In between the 4 kingdoms there is an unforgiving landscape filled with deserts, mountains, forests and lakes. It is called “no mans land” they have various clans and tribes and principalities here but no set ruler to date. Anyone on the run from any monarch or not wanting to live under anyone's thumb and unable to go anywhere else travel here to live. Getting here is easy surviving it is much harder. They do have rumors that there is a demon, a very old demon , That lives somewhere in the center of this harsh land and he will grant favors for a price. Is what you want worth your life?