Okay, a lot of business to attend to here:
First, there’s been a small influx of A.I.-generated comments on the site, with links to A.I.-related companies. It’s particularly insidious, signing themselves in with real-sounding names and generating comments from stuff either I or other commenters have said. A couple just sounded like they were agreeing with me, but more often than not they were just slightly rewording what we’ve said. Ugh. Look, I think A.I. can have its uses (once they solve the whole, you know, energy/water usage thing), like in dealing with and sorting data, but we don’t need Newer, Better Spam. So, I’ll try to nip these in the bud as I notice them.
Second, I’ve got medical stuff going on in the middle of the week, so Wednesday’s post is gonna be quite short. By which I mean “actually, really short,” not “I’m going to keep this short” and suddenly I’ve written an Alan Moore script.
Third, some of you had some good suggestions regarding the earliest regular cover/opaque-bagged naughty variants. Brian F sends me to this NSFW reference page that may require some digging.
Another likely suspect, provided by Matthew, is Hellina: Taking Back the Night did have a polybagged nude variant (NSFW again) according to advance publicity, with obscuring black bars. Here’s one I found on eBay:

Out in 1995, a year after the Perg comic I talked about last time, which was in an entirely clear bag.
Barring my finding something in that list of books Brian sent me, that may be the earliest example so far of “adult variant for a non-adult book in an obscuring bag.” Even if, you know, that “obscuring” is restricted to a couple of small black bars, and not covering the entire image like the newer variants that triggered this whole discussion.
Fourth, in this post discussing some X-rated comics of the ’90s that had merit, some of you brought up Phil Foglio’s XXXenophile, which is indeed one of the great filthy books of the period. Wonderful art (mostly Phil, with a parade of inkers/finishers), short and clever stories, and, yes, lots of, ahem, shenanigans. It’s all joyful and hilarious and will likely offend somebody at some point. Like, I’m not going to vouch for the political correctness of this cover, but it’s plenty silly:

Again, there were plenty of adult comics that were well worth your time and attention, and XXXenophile was among the best of them. Like I said before, I’m not sure what sort of coverage of them I can get away with here, but at the very least I can acknowledge them.
I know it’s no longer going to be recognized as one worth seeking out by most now due to the author, but the Cherry Deluxe comic written by Neil Gaiman was an erotic comic I bought and found enjoyable.
I don’t think I have many of these type of comics in my personal collection, unless we are counting the actual underground comix (not that I own a huge amount of those either), things like Omaha the Cat Dancer, the Taboo anthology (with Moore’s unfinished Lost Girls included, alongside a lot of other really great stories), or an indy comic like Yummy Fur. I don’t really consider comics like these ones in the “X-rated” catergory, unlike Cherry Deluxe, but I don’t know the exact criteria, so I’m not sure what else would really count.