Late in season one, Guillermo discovers that he is a descendant of the famous vampire hunter Abraham Van Helsing, and he proves to be very skilled at killing vampires (including by accident), giving him conflicting feelings about his desire to become a vampire. Guillermo's skill as a vampire slayer leads to him becoming a bodyguard for Nandor, Nadja, and Laszlo in the third season. He reveals he is gay in the fourth season, coming out to his family, with Nadja having to erase their memories about Guillermo's confession about wishing to become a vampire.