3145, before the storm
Seven years after The Great War that wiped seventy percent of human population, the earth is facing a crisis with the nature destroyed and many of its species went extinct. The last people that still survived got divided to only two areas: an autocracy nation and a dictatorial kingdom.
It was also at this time that the Big Discovery happened. On the brink of extinction, humanity was forced to do its best in order to survive, pushing them to advance more and more in almost every aspect, making up for what they lack naturally with the technology they created. When the first [some fancy technology] was created, humans discovered a lifeform entirely different than what they've ever seen before. Djinns. Astrals. It turns out they weren't just a myth after all.
With years passing by, humans figured out how to live among them. Some married them, even though it's heavily frowned upon and would often result in banishment. Some other... they make deals with them. It's a game of using and being used. What humans haven't figure out: the astrals are far far more cunning and smart than they appear to be.