Why
There is a town, it's a heavily populated town at that. It's surrounded by woods, and gates to the town. Just inside one of the gates is a large mansion. No one knows how tall it is, because no one has ever been inside. The one kid brave enough to go inside....never came back out. One day, just like any other, a letter came to all the houses in the town. It was requesting any one that wanted to party, to come to a party at the mansion. No one knew who sent it, but one thing was for sure...whoever owned the mansion, be it human or creature, would show themselves soon enough.