The broad main plot: A human who accidentally arrives in this world wants to turn it into a cyberpunk world, caught between a war with the emperors of the old era and demons.
The truth: The early stages are all about building strength. You need enough power to change the world, or you're just another nobody. Later, it's all about settling down and steadily growing stronger. Don't take unnecessary risks. Keep your head down, and you'll soar.