Without warning, human civilization goes to ruin overnight. However, those who survive the apocalypse are not necessarily the lucky ones. For there are also plenty of psychopaths and sadists who have survived, embodying the evil that has always existed in humanity. And then there are the cruelly transformed, who have turned into perverse, insatiable, and bloodthirsty barbarians without restraint due to a mysterious infection. Anyone wandering through this hopeless new world will sooner or later encounter some brutal monster—or inevitably become someone who commits unspeakable acts to see another day.