Within each living being is a spark of light. Without this light, no life could exist. Opinions differ on where this spark of light comes from. Some say it was a gift from their gods. Some claim it evolved spontaneously. All of those in possession of this light are free to do with it as they choose. Like any light, it can dim and grow dark over time or its shine can grow brighter. It is ultimately up to them. There are those who discover that this pure light lives within them and learn how to use it. These people become sehashi, defenders of their worlds.