Crowley wouldn't have pegged her for French at all. He had to admit it was a touch rusty on his Archaic French, but it was one of those languages that once you knew it, you knew it forever. He just might have been a bit slow in making the mental transition from English to French in the ear she seemed to be speaking from.
It appeared that not only did the City pull from all areas of the world and mythical relations, it pulled from different periods in time as well. Crowley advanced closer and offered her a hand, though he probably shouldn't have as that was the kind thing to do. But he found that without Aziraphale there to counter his negativity, he was easily stepping into both shoes. Both his and Aziraphale's.
Stupid angel had tainted him. He was Crowley. A demon. The demon that had been Crawly the serpent in the Garden of Eden. And here he was, helping a newly deposited member of the City. He was doing that a lot lately... helping people. A dangerous past time for a demon. You lost your reputation that way.
"Let me help you stand," he said, echoing her French, now that he'd had a moment to make the mental transition to thinking in the language. She had taken quite a fall, one that prior to coming to the City, prior to ending the Apocalypse, he would have laughed at. But now he just felt sorry for her. Stupid affection for humans. It was ruining him.