Well, it was slightly less embarrassing than the Doctor's daughter walking in on them. At least they were wearing more clothes this time than the last time Jack had interrupted.
Rose was trying hard not to laugh. It was amusing, just a little bit! It had been hard to get rid of Jack last time, though. And the fact that Rose was entertained wouldn't get him out the door any faster.
She focused instead on the Doctor, leaning in to kiss his neck lightly. "Don't we have a lock?"