In a world of apocalypse, wars break out across the globe, and the surface is overrun by "walking corpses."
　Two young female soldiers have been hiding in an underground shelter for a long time.
　To endure these extreme days, they keep repeating the routines of their daily lives.
　
　A brutal past, a stagnant present, and an uncertain future—
　This is the story of those living in the deepest depths of hell.