Boy did Martha understand that. But as far as she's concerned, all vampire myths are probably more due to aliens like Torchwood's Janet. "I wouldn't be surprised if we did have something similar to vampires on my world. They'll show themselves all in good time." She doesn't seem too concerned by that fact.
Actually, Martha's more concerned about the robot coming through the door. "And that's my cue to leave," Martha quips as she sets her water down on the bar. She moves laterally along the bar, simultaneously trying to get as far from the robot and from Eric as possible. Even so, she wasn't sure she'd be quick enough. The robot was blocking her exit and making it difficult for her to get too far away from either.