Vampire. One of the five 'night students' at Mansbridge Academy selected to take part in the Mansbridge Experiment. Although she initially appears mild, bookish, and soft-spoken, it becomes clear that Merrill has a dark and even malevolent side she tries to keep suppressed. She believes that Drew is her 'One' (which is the vampire equivalent of a soul mate), and is deeply upset when he falls for Mansbridge 'day student' Sherry. In her jealousy, she possibly causes the appendicitis attack which ends Sherry's life, a possibility that haunts her afterwards, despite Dr. Murdoch's assurances to the contrary. She later begins to develop an attraction to fellow vampire Marty, despite the differences in their personalities. Out of all the young vampires participating in the Experiment, she is the one who is most determined to make it work. She is also the only vampire on the series whose Maker is identified, namely Patsy LaRue. Merrill has the power to read other people's minds and dream slide. As a side note, she keeps a pet rat she calls Bela.