A few weeks ago, coming home on the train, a couple of giggling schoolgirls trying to impress a tubby boy with a discussion of anal sex. "Every hole is a goal," I remember, and "If it's red, take the brown." Not seen exactly as routine, or even firsthand, but well within the universe of discourse in a public space.
And today (different kids)
"and then I went home and had a bath...."
"Eeew. That's weird."
"What's weird about being clean?"
""Well, showers, yes, but just cleaning all the shit off your body and then sitting in there with it..."
Generational markers, both of them.
Or, on reflection, possibly not: I remember my friend Rutherford back in 1967 or thereabouts expressing himself in strong terms on his repugnance for, as he put it, "stewing in your own secretions".
But at the time that was itself seen as a rather weird response.