If anyone understood the universe being confusing, it's River Song. Not to mention, she's not surprised by 'Sexy's lack of picking up on the innuendo and just found herself tempted to run with it a bit.

Then again..."Sexy. Is that what he calls you when no one's around?" As incredulous as she sounds, River's not really surprised.

"I'm not sure if I should feel jealous or honored that I share my husband with you if he's calling another woman sexy behind my back." Lets face it, River's never going to let The Doctor live this one down next time she sees him.