While writing the third book in my techno-fantasy series, I still struggle with the details of the second one. I’ve cut down on the exposition in the story proper, and instead added an explanatory intro. Here it is, translated to English:
Humans versus demons
After the thirteenth century Armageddon crisis, we kept up with the demons for centuries. A growing human population attracted an increasing number of demons, but also produced more children with magic abilities who could be trained in exorcism. Demons grew stronger, but humans developed new magical techniques. The combo ritual, discovered in 2013, lead to the creation of whole compatible exorcist teams, capable of taking on and defeating demons with a strength never seen before.
The only factor in the human-demon equation which remained constant was the amount of raw magic available for exorcists to channel at any given time. In the 2050’s we hit the ceiling. Blocks dropped and rituals failed. Demons possessed, killed, and pulled people down to Hell; exorcists would helplessly watch while waiting for the magic levels to once again rise sufficiently high for a ritual.
Humanity regained control by shrinking. The Global Bureau of Population Control was formed, with an initial complete ban on childbirth for twenty years time. This was not well received. The Twenty Hard Years were dominated by war and unrest, ranging from smaller skirmishes to the nuking of major cities. During the 2070’s the situation stabilized, while the human population continued to shrink through severely limited and controlled reproduction. Once again, we had enough magic. The demon threat was under control. Demons still got stronger and stronger, but the exorcist teams could handle them.
However, the average rev up time for demons shrank down to a few hours from emergence to attack. It was now vitally necessary to always be close to an exorcist team. In the 2130’s, The Great Urbanization started; all of humanity concentrated in cities. Once again, the situation was under control. For the time being.