Originally Posted by stcoop:
“Humans looks like Time Lords and Time Lords look like humans. We've know that since 1963. Expecting something more?”
In the context of the scene, christina has just said, "remind me not to kiss them." (referring to the tritovores)
just a few moments later, after Doc has explained he's an alien, he says "but you don't have to kiss me either".
At which point she says "but you look human", "and you look timelord".
the pause is them thinking about the "kiss" aspect. That's all - mutually silently acknowledging they fancy each other.