The answers to the other comments, such as elementals or a cutting remark about Jack's chances were forstalled by the Doctor's blank look and his question.

It was briefly surprising, given that her own Doctor had been the one to introduce her to the concept that 51st century humans were obsessed with 'dancing' with anyone and everyone they met. (So maybe he exagerrated) But this was a different Doctor, and 'dancing' wasn't exactly on the same linguistic level as 'three way'.

"It's..." She blinked, and directed a distinctly 'mind your mouth around the kids' look at Jack. "Nothing that's ever happenin'."