Shi no Yosai

The Fortress of Death, or Shi no Yosai in the native language of the Kamejin, is a fortress that sits at the center of Kyokai Shima, the Border Island of the Abral Island Archipelago between the east and west of Totania.

The Military Fortress

Made of an unidentified black stone, assumed to be some form of obsidian, it is said to be impossible to break the walls of the Shi no Yosai. Its peak reaches 161.5 meters or 530 feet tall, and its width is that of the isthmus of Kyokai Shima. However, at the center of its base level is a canal for ships to pass through, which is often where a majority of the Kamejin navy is kept.
On its roof sits the Dragon Gate, made of obsidian and Fuccium in the shape of a Dragon. It is the only prison said to be able to hold a Dragon captive.
Gates to either side of the island are on the base, and barracks capable of housing thousands of soldiers can be found inside.

Tsuji-Torworth

Tsuji and Torworth are the two largest settlements on Kyokai Shima. Tsuji, the wester settlement, was built by the Kamejin and Torworth, the eastern settlement, was made by the Lizardfolk.
These two places are often at war, since the First Tsuji-Torworth War, hoping to gain full control of the island.
Shi no Yosai sits between these two towns, and is always controlled by one of the two factions against the other.

Residents

The Shi no Yosai, being the seat of power for the Abral Empire's military, is home to thousands of soldiers, as well as some civilian forces and specialized groups that make the fortress their home. These residents are as follows:

Naval Forces

The navy especially is headquartered at the Shi no Yosai, with most ships that are not actively patrolling being found instead at the Shi no Yosai. Some enemies to the Kamejin have said that if those ships could be sunk, the Abral forces would be crippled and invasion of the Abral Islands would be much easier.
This would require one to get past the entire navy and a large portion of their ground troops as well to take out the ships, which has proven an impossible feat.

Ground Troops

Member of the Ryuukihei by Jarhed

Compared to the navy, not many ground troops reside at the Shi no Yosai. Instead, they are spread around the islands, mostly in the capital city of Kochi to protect the vulnerable position and the Emperor.
Some, however, do stay here in case of attacks from the Lizardfolk, and more arrive if and when war breaks out.

Ryuukihei

Also called the Dragoons, the Ryuukihei, are an elite force of female Kamejin raised around reptiles, trained on how to treat and raise them, as well as how to subude and kill them. Their main task at the Shi no Yosai is to guard the Dragon's Gate.
They fight with a special, blunt style of fighting similar to the way a Dragon does, and they have special masks that breathe fire.

Shinsengumi

The Shinsengumi are an elite group of specialists chosen by the Emperor to do various tasks. For many Emperors, this means they gather warriors. This is not always the case, as the Shinsengumi does not need to be explicitly soldiers. They are merely skilled people from around the Abrals who can serve directly to the Emperor rather than in any other Chain of Command.
Some, particularly if they are in the military, like to stay in the Shi no Yosai to keep themselves closer to the troops, but not all members of the Shinsengumi do so.

Emperor/Empress

The Emperor or Empress may at times stay in the Shi no Yosai. It does not happen often, as they usually stay in the Imperial Palace of Kochi, however this can serve as a seat of their power as it already does for the military. Since it is the seat of power for the military, some Emperors and Empresses like to stay here to get closer to their soldiers.