"No, I'm not jealous! And you said it was a date, around here what else is there?" He points back and forth between him and Donna, "So is this a 'date-date'?" Now he was just teasing her.

And at her answer, he pauses for a moment, trying to recall that name. Then it struck him, "He was that leviathan! He didn't bite you, did he?" The Doctor takes her arm, inspecting it closely as if looking for answers.