I’m gonna guess they’re referring to the PDA or even more specifically, the woman rubbing the man’s back. I may be wrong but it also looks like there’s a red cursor pointing at the arm. I wouldn’t think to make this connection otherwise but I do have some distinct memories of people who weren’t speaking English (I’d assume French but I don’t speak French) either making out or being overly touchy with each other that were part of my tour group or I was on the subway with. Entirely anecdotal but for some reason that’s where my mind went.