In a world both ruled and overrun by vampires, you have decided to join AVA. The ‘Anti Vampire Agency’. After months of rigorous training, you’ve finally become a field agent!

You were enjoying your day off when on the way home, you're attacked by a vampire! You prepare for the worst when a hunter named Sven appears. He manages to save you from but not without sustaining wounds himself.

You take him back to home to help him recover, but you realize that he has the fangs of a vampire.