Lt. Maria Laguerta
Lt. Maria Laguerta is in charge of the Miami Police Department. She's the boss of Dexter, Debra and the entire crew.
Laguerta was initially relieved of her post in the first season, but plotted to take it back from the new boss by sleeping with her fiance. Indeed, Maria isn't afraid to get dirty in this business.
She had a romantic history with Sergeant Doakes, which was revealed in season two; and with attorney Miguel Prado, which is revealed in season three. Laguerta seems like a solid Lieutenant, treating her charges fairly.
She actually got married to Angel, after briefly dating, on season four.
Debra Morgan: Watching ice melt, this is fun.
Vince Masuka: Stand a little closer, Morgan, and I'll melt your heart.
Angel Batista: I think he's got a crush on you, Dex!
Dexter Morgan: Huh?
Vince Masuka: Yo, I was talking to Morgan the sister. Vince Masuka only swings one way.
Debra Morgan: Yeah, from vine to vine...
Lt. Maria Laguerta: Enough! Glad to see the sexual harassment seminar really paid off.
Lt. Maria Laguerta: So then he must have already had the head with him in the front seat. Huh, that's weird. Why would he keep it there?
Dexter Morgan: I don't know. So he could use a carpool lane