AFAICT, it must be for one of two passages. The first: "It's about actual sex, real sex, between real people, not circus freaks playing to the camera. Sex is different from porn. Usually. If you're lucky." The second in the next comment. - walt crawford

"How was it?" Peebles asked... "Good. Great. Strange," Chris said. "Not like masturbation." (para) "Yeah, they're remarkably different." (para) "I kept worrying about her, what she was feeling, and she kept worrying about how she was doing, how I was feeling, I could tell. Toward the end, though, we sort of forgot to worry. We stopped thinking. I think." - walt crawford

"She said I was the best she'd had. I said the same thing to her, obviously. But it was sort of nerve-wracking." - walt crawford

So: is it the word "masturbation"? The idea of premarital sex? Certainly not lascivious details--you've just read all the details there are. I'm stumped. (The "nerve-wracking" is because this guy hasn't been able to relate to people, but is now taking empathy pills.) - walt crawford

Ah, but then I'm one of those who finds it remarkable that a PG13 movie can have as much bloody violence as anybody could possibly want--but only one F-word and precious little if any visible "nasty parts." Because violence is healthy but sex is nasty, apparently. - walt crawford

I want to know how old they think "younger readers" are. Those passages are pretty tame by YA standards. - Katy S

That's my feeling. I don't think either of the other two of the "big three" SF/F magazines would have included that warning. ("Big three" in scare quotes because none of them have really good circulation, unfortunately.) I'd swear there was nothing in the story that was even remotely offensive or Adult. - walt crawford

Seems like the writing wouldn't attract those too young to read it?<maybe would have better if I left the autocorrect - Christina Pikas