Gensokyo, a world which exists quietly beside ours, separated by a mystical barrier. A utopia where humans and other beings such as fairies, youkai, and gods live peacefully together.
But what is Gensokyo?
About one hundred years ago, humanity had begun to lose faith in the existence of the supernatural gods and youkai in the world. Greatly pained by this loss of belief, the youkai banded together and sealed a part of the world away behind the magical Hakurei Barrier, maintained by the shrine maidens of the Hakurei Shrine. This land was named Gensokyo.
Youkai, fairies, devils, and all other manner of supernatural beings from around the world began funneling into Gensokyo to escape the fate of being forgotten by the outside - Akin to death for such creatures. Within Gensokyo, the humans dealt with supernatural creatures on a daily basis, and there was no risk of being forgotten.
Up until recently, though, humans lived in fear of youkai. Youkai would still hunt, kill, and sometimes even eat humans in an effort to keep their powers strong. The recent addition of the Spell Card rules has put an end to this, though. Youkai and humans are seen together a lot more often, as part of a peace accord organized between the most powerful of the youkai and the most recent Hakurei shrine maiden. Though superstition and fear still exist, things are much more casual in the modern Gensokyo.