All know that Elves cannot die, and that Men do. All know that Men go unto the Underworld upon their death, and that the Elves retire unto the Spiritual Elysium. Yet in the Great Scheme, where goes the one with one foot in the Underworld, and one foot in the Realm of Spirit?
This really comes from an ancient Chinese novel. Imagine during the PCs' travels, they come to a place where the gender roles are completely reversed. What adventures will the PCs encounter in such a place?