A mysterious meteorite called "Original Sin" falls and releases a strange energy called "Scarlet Mist". This drastic change is not a natural disaster, but a screening experiment of some kind of civilization deep in the universe. In 2035, the scarlet fog broke out, and human civilization was overturned overnight. Mutated creatures hungry for flesh and blood were born in the fog, and the energy in the air not only brought death, but also opened up the possibility of human evolution.
