In the episode, "Bad Blood", Liam O'Neal comes to Toronto because the details of the murder case make him suspect that a vampire may be involved. Janette identifies O'Neal as a Hunter, i.e., a human who is aware of the existence of vampires, hunts them down, and kills them. The possibility of such vampire hunters provides an obvious plot for fan fiction; and the term "Hunter" is a common way for fan writers to refer to them.