Ms. Clench (Catherine Lough Haggquist) is the main villainess from "Blood Drive," an episode of Hub Network's short-lived series, Spooksville (airdate April 5, 2014).
Ms. Clench is an evil 500-year-old master vampire who posed as a teacher at Adam, Watch, and Sally's school. She started a blood drive in order to fulfill her hunger and then got to work on her evil plan to turn all of the students (including Watch and Sally) into vampires. Ms. Clench's villainous reveal came during the big dance, while Adam was fighting against the vampire students on his own with holy water. She flashed her vampire fangs at Adam and was set to turn him as well, only to be thwarted by Principal Blackwater, a vampire hunter (her real last name is Van Helsing). This led to a battle between Blackwater and Ms. Clench, which ended with the villainess staked with a pencil through her heart.