There is a reality beyond human understanding, a reality in which powerful beings greater than anything humans can understand, operate behind the scenes to manipulate the fate of Earth civilization.
For genetic reasons, human females are more impervious to their powers than the male of the species. The benign beings who protect humanity from outside control know this and realize that it is their duty to create more young females to fight the forces of Evil. Specially-selected boys are contacted and asked if they would be willing to become girls to protect and defend humanity. The ones who agree are feminized and given special magical powers by the Sisterhood.
These boys-turned-girls must deal with the emotional upheaval caused by their new feelings and attractions while simultaneously doing battle with the spirits who would destroy life as they know it.