The year is 2051. A new strain of virus has mutated 5% of the Earth's population into creatures of the night. "Vampires," as they're called by their detractors, tentatively co-exist alongside humans thanks to Aeternus Eternus, a synthetic form of sustenance created by Biotech giant Imago Labs. But for some, nothing can truly replace the taste of fresh blood...fresh human blood. As the illegal blood trade rises, a new predator takes to the streets. One which even the Vampires themselves fear. Those who have seen him and lived to tell about it can only utter one word to describe the winged avenger, hell-bent on ridding the world of their people. "NOCTUA."