"I know. And I'm sorry that there's nothing I can do about that." Show no reaction. No annoyance. Just concern. "But I suppose Jack would never be prepared to hurt you, and... it's necessary."

'Jack'. Not Harkness. Powerful thing, familiarity.

"You know, they train us," he says, letting the hand slip in toward the collarbone. "So we know every bone and muscle in the human body. Every nerve and gland and reflex. And after a while, that's how we see people - these muscles, these sensations. It takes a keen interest in bodies to be good at what we do."

Up along the collarbone, fingers resting in an arc over her pulse.

"It makes us good at this. It's not the only thing it helps with. You've got a strong heartbeat."