The hyperborean realm of the Eternal Flame
Clarence was singing in harmony as his kind is wont to do. Their singing reinforced the "song of existance". It was a somewhat important job, even though only a handful were needed rather than the hundreds that did so. He and others near him noticed the pin prick discordence in the weave of melody that was the material realm. Those dark alien notes rose up. The Angel Mind touch the Divine and followed the new sub melody. Humans would call it a plan. Angels dove to the material realm and, of course, if any world was going to be causing problems, it had to be Earth. Oh well, at least Clarence would know his way around.
There are reports of a monster that lurks in the tops of trees and drops down on unsuspecting people. It causes them no damage but it frightens them with a hide-like face with big dead eyes, drooling and barking like a dog while unsuccessfully attempting to have intercourse. The PCs investigate and find that it is the local village moron that is doing the spelunking in the woods. How can they explain this otherwise pleasant and merry man that it is wrong to put on a mask, drop down from trees and attempt intercourse with relatives and neighbours.