The planet Cocoon is called by many names.
The star that receives blessings, the star surrounded by light, the star blessed by Solaris, and the star hidden in darkness. The names of the stars vary depending on the region of the Cocoon and the different ways of thinking about them.
Cocoon has five moons as satellites in the sky. The moons shine a faint light on Cocoon, but the light is not strong, just moonlight. Another star, Solaris, which illuminates the Cocoon with light, is also visible out in space. Its light is strong and illuminates half the world of the Cocoon.
Although the moon and Solaris are visible in the same sky, beliefs and understandings of their existence differ considerably among Cocoon nations, leading to the differences in the way they call their Cocoon.
The country that considers Solaris to be "a star blessed by the moon" is called the Twelve Sacred Knights.
The Twelve Sacred Knights are the nation that protects the order of this Cocoon. It is said that the country was once founded by 12 gods, and that they were succeeded by the Twelve Sacred Knights, who rule the regions within the country. However, no one has actually seen this tradition, and it remains only as a tradition. But there is no doubt that it serves as an icon of veneration and respect for the people.
In this country, people believe that the Cocoon is protected by blessings from the moon in the sky, and they have faith in the moon. It is an undeniable fact that moonlight sometimes gives us magical powers. In particular, stones that have been bathed in moonlight for a long time are called magic stones and are known to be the source of magical powers. In addition, each moon has its own characteristics, and stones blessed by the Light Moon, Flame Moon, Water Moon, Wind Moon, and Darkness Moon are suitable for using magic that makes use of their characteristics. There are affinities, and the magic stones born from the water and light moons are mainly used in the Twelve Sacred Knights.
It was the Twelve Sacred Knights who adopted the Cocoon Calendar. The reason was that a description of the "birth" of Cocoon was found about 1,000 years ago. They do not know who wrote this description, but it was based on this description that the current Cocoon Calendar was established.
The counterpart religion is the Solari, a Religious Nation. Its religion places its faith in Solaris, which emits light from beyond the universe. They believe that Solaris is the sun, which blesses the planet, and they call Cocoon "the blessed star of Solaris. For Solari, Solaris is everything, and the moon is merely a satellite.
But its teachings have a caustic side. The most prominent is that heretics are not tolerated, and carrying out their sentence is the Heresy Hunters, who constantly patrol this nation. The Heresy Hunters are led by a symbolic saint, known as the Punisher, currently called Mika. On top of that, there is a Solari guru, but no one has ever seen the figure; there is a room where generations of saints can receive teachings from that guru, but only saints can enter, and even then, only by voice and never by sight.
Where the Solari teachings originated is one of the questions for the rest of the world. Some thought that the "Solaris" in the sky had some kind of will and was interfering. One of the reasons was the presence of "mechanical" life forms that were different from the creatures that existed in this world. One researcher happened to catch a creature that was moving in a mysterious manner. He discovered that the creature had been "modified" by someone. It had been created with technology that could not be found anywhere else in the world.
The country where the researcher was located is an Eternal, Artificial Archipelago, where there are many intellectuals who think of Cocoon as a "planet enveloped in light. They are always interested in the great mysteries of this world, such as why there are five moons? What is Solaris in the sky made of? They believe that there are many secrets hidden in this cocoon. He was convinced that many of them were hidden in the back world. Now he thought that the light from Solaris had something to do with many of these mysteries.
Cocoon's back world. The light of Solaris is strong, but only half of the cocoon is illuminated, and the cocoon always faces the same direction toward Solaris. The light of Solaris only reaches the front world, not the back world. There, only a small amount of light reflected by the moon reaches the surface, and it is only the light of a firefly in the night, and therefore, no one is allowed to move to the back world without special permission.
One of the hypotheses of a scientist at Eternal is that the surface world of Cocoon is enveloped in the light of Solaris, perhaps "illuminating" it in order to grasp our activities? This country considers Solaris as a research subject. But this has often provoked a backlash from the religious state of Solaris.
"A star hidden in the darkness". This is what those who are interested in the back world call Cocoon.
In the valley between the front world and the back world, there is the Underground Fighting Arena. Here, not only those who like to fight, but also stragglers and recluses, gather and fight feverishly night after night. Sometimes visitors from the back world and monsters also come to the arena. This is the end of the line for ordinary people in Cocoon. From here on, it is a complete back world, and one must overcome the dangers and darkness in order to proceed.
But even in the back world, there is a place that might be called a sanctuary. It refers to a single tree and the area around it. Around it, a clan is said to live who mourn those who have come seeking a place to die. Rumor has it that "vampires" also appear there, but this is not certain. In the front world, vampires are only a figure that appears in folklore and books.
What is certain is that this is only the entrance to the " back world," and that there is an even larger and more dangerous area spreading out from there.
However, the time may be approaching when the light will shine on the back world.