Everyone is Single - TV Tropes challenge

I was given Everyone is Single as part of the TV tropes challenge, to write something in response to the trope.

So, I bounced back and forth on this, between whether I should write fic or meta. Ultimately, what decided me is that I really wanted to write Narnia for this, but the characters refused to cooperate. So I guess we're all stuck with meta, then.

( spoilers for NCIS and New Doctor Who below )