Where The Light Doesn't Fall

The dark is brighter than the light outside.
All of known humanity has been forced into hiding, only a few daring ones roaming the surface. Humans have been endangered by a danger powerful enough to wipe them all.This danger is the infamous 'Vapors'.
Legend has it once it sees you, consider yourself already dead, for there is no escape once you walk into their clutches.
It's Luna Grey's first day seeing the world she once forgot ever since she was confined to a dark bunker for 11 years, but she slips into the danger of the outside world by doing so.