#4: LILA TOURNAY, A.K.A. LILA WEST (JAIME MURRAY)
Season: 2 (10 episodes)
Killer bio: A homicidal arsonist, Lila solves problems like Dylan from Da Band—with more fiyah! More fiyah! More fiiiiyaaaah!
What she does to Dexter: Lila believes that Dexter is her sociopathic soulmate, which has its benefits (she protects him by blowing up the pesky homicide detective who’s figured out that Dexter is a serial killer). She doesn’t take rejection well, though, and frames one of his coworkers for rape, then attempts to make Dexter and his other chick’s kids flambee. Getting burnt with gonorrhea seems halfway decent in comparison.