Dark, creepy, plausible, and... marvelous! :D
Oh my goodness, this is just chilling. I hate seeing the Doctor so lost, and then in my darker thoughts, I wonder if he is lost at all in this story. *shudders* Well done.
Instant favorite. Creepily plausible. Great continuity with earlier regenerations. This is the same Doctor who was totally fine with letting the Gelth borrow some corpses to wander around in - it's a different morality, get used to it.
Also - "you're a beautiful woman, probably." Yes! Four!
Yes! I've been waiting ever since the episode for someone to write this fanfic. Well done. Dark and convincing in all the right ways.
Interesting, and very disturbing UA.