Legendary creatures are now the main population on Earth, with vampires, werewolves, mermaids, and others out in the open around the world. Humans, however, have become a thing of legend themselves. Spritus, or their ghosts, are the only remaining fragment of human life. A popular past time for young Monstrum is to go seeking such spirits. Sawyer (a vampire) and Munny (a werewolf) particularly love going spirit hunting. On one outing however, in an abandoned hospital, they come across the most mythical of beings- a human girl.