In 2049, the "Red Moon Catastrophe" broke out on the earth, and 80% of the human race mutated into bloodthirsty. The survivors awakened their special powers in the revival of spiritual energy. The protagonist obtained the "devouring evolution system" and could obtain evolution points by killing bloodthirsty, but he had to devour living beings of the same kind to break through the realm.
Purpose: Civilized and moral right to exist