About eight centuries ago, thousands of interdimensional gates suddenly began opening across the world. From these, terrible paranormal creatures penetrated into our reality. Their power was incredible—some were so strong and so huge that they smashed everything in their path and nothing could stop them. Others were parasites: they latched onto people, drained their life forces, and turned them into obedient slaves. And a third kind were cleverer—they infiltrated cities, disguising themselves as ordinary residents, and attacked them under cover of night. Welcome to a world where the human race sank to the bottom of the food chain, and the world turned into a paradise… a paradise for monsters…