I think you should have said that earlier instead of "Isn't this a bit odd?"
But it is now in the past. Now is the time for moving on!
I think it'd be child porn if people masturbated to it while thinking "Mmm, children...", but as it is, it's just somewhat suggestive anime art of underage characters. I wouldn't have thought of them being in a sexual situation if you hadn't suggested it. To me it was a pretty cool picture of Asuka and Rei with an unneccessary panty shot that is common in most anime-related-stuff and doesn't always mean "BUY THIS BECAUSE IT IS ALMOST PORN."
So I don't think it is similar to child porn. It's bizzaro art.
[edit] But since you don't even care anymore you can just ignore me
