We did what you’d do in these situations.
It’s funny how these things work themselves out, isn’t it?
I remember once hurrying along a canal towpath as a shortcut to get to a pub before last orders.
I was striding along when I saw in the gloom a carrier bag or something blowing in the breeze.
After a couple of steps I realised it wasn’t windy.
Couple of steps more and I realised it was moving kind of rythmically.
Couple of steps more and I realised it wasn’t a plastic bag at all but a young lady’s bottom shining out of the darkness as she straddled a fellow on a bench.
At which point I had something of a dilemma. Politeness dictated I should quietly withdraw. But, as I have indicated, I was minutes away from last orders at the boozer, which I would surely miss if I were to retrace my steps.
So I did the next best thing and pressed on past them pretending nothing was happening. And they pretended much the same thing. It was kind of a triumph of British reserve all in all.