In this land, humans and vampires live in divided territories, constantly waging war against one another. Humans take up professions like Vampire Hunters to resist, while vampires work to overcome their weaknesses and hide among humans, waiting for the perfect chance to strike. Both sides live with weapons pointed at each other's throats. Beyond humans and vampires, other races live in hiding, most of whom have been driven to the brink of extinction by the vampires. Vampires are strictly hierarchical, categorized into Lower, Upper, and High-ranking classes.