As far as I'm concerned, Doctor Who's Strax, the Sontaran commander turned fancy butler, has been one of the MVPs of NuWho. With his firm, military delivery, his limited ability to identify gender, and a brain as potato-like as his precious visage, Strax is gloriously lovable for a million reasons.
Reasons like his commitment to the lactation arts. Specifically, splicing his own genes to provide sustenance as necessary.
He's great with animals.
He's wonderfully useful, nothing if not direct, and endlessly focused on the task at hand. Well, whatever he seems to think the task is, regardless of anyone else's goals or needs.
Sontar ha, y'all.