One day, a never-ending night came to the world. The huge moon did not move, as if it had been stuck on top of the sky on a pitch-black night., and the sun never came to mind again, and mythical beings who only existed in myths or legends began to appear in Darkness.
The existence of this other world, which came with the eternal night, has slowly but surely eroded the realm of humans, and has come to realize that humans can no longer live in Darkness without acknowledging the existence of these devils.
After ten years, The first contactor and the Contract Devil 'Azathoth', who created the eternal night and brought Devil to the ground through the gate, fled to another world after being driven by a hero called Contractor of Light, but the night was still in darkness, as Azathoth's strength was still in full swing.
After another ten years, people began to adjust to Darkness. Some of them considered Devil's relationship with humans an opportunity. Some tried to build wealth using Devil's power, some built a religion and reigned over people, some busily trying to figure out the cause of the night and restore light.
A new order was blooming rapidly in such chaos. However, there was a limit to the order people created themselves.
People felt the need for a new organization to establish order, a 'new government,' and wanted to form a new coalition centered on contractors. The new transcendental government, named Yggdrasil, seemed to bring new order and peace to the world at first glance.