There has always been man.
Mankind, supreme among the animal kingdom, has progressed far from the medieval days, when his tiny villages could be attacked by vampires, from when he could fall victim to the demons of the darkness, and cower from the shadow. Mankind has built great cities in the wastelands, the skyscrapers he has built towering up to the heavens, his spaceships taking him to worlds his primitive contemporaries could only dream of. Mankind has soared, and mankind has achieved. He is truly the greatest of God's creations.
The vampires would disagree. Powerful, fierce, proud, and predatory, they resemble a human in many ways. Their ears are pointed. They have little body hair. They are taller, and their tongues are grooved, and their teeth are long and sharp. Their nails end in blunt claws. But who, among the teeming masses of humanity, would notice such things? Who would deliberately search the seething underbellies of the dark cities of mankind in order to find these predators?
They do not threaten man. They only exploit the species. There are species of spiders which resemble ants, and manage to gain entrance to the ant colony in this way. They can then feast without being noticed. So too it is with vampires, and man can never eradicate them. They are the scourge of God, keeping the human race from hubris, their presence a constant reminder to the proud and lofty human that he is little better than a sheep or cow to the monsters who live in his domain, who hunt him and his children, and will do so until the end of time.
So, what do you think? What direction should I take this? I will try to incorporate responses into future chapters.