A clothed bum is pg-13, trust me some of the things that get by sensors these days.
If it was a nude bum or a bum in panties, of course, but a bum in a dress or in some jeans is in no way offensive.
I might just be admiring the bakc of the dress for example.
I have about zero issues with seeing the human form, but there are some things that cannot be unseen - reference back to the walmart pics.
I was in a shop yesterday buying some items completely unrelated to nekkid people, art, or clothing. Unbeknownst to me, the shop owners are selling some of their artwork. Very interesting creepy sculptures - would freak hubster out (much to my delight) and the other artist is a retired from tattooing. He showed me some of his artwork, including some rather provocative art. I'm not an artist by any stretch of the imagination, so I love seeing ALL of that stuff and having a chance to speak with the artists to find out what inspired them.
Now pics of random butts? Y'all, I am old but not naive. I could tell you stories that would make you blush. Butts, boobs, etc., not a shocker to me. At most it would make me turn into a giggling teenager.
@Elmira: Plain ol' nudity doesn't make me laugh anymore, but romantic scenes in books and on shows make me giggly! Actually, I laugh so hard no sound comes out half the time.
Now I have a montage of Yellow Polka Dot Bikini and Big Butts in my head. Perhaps Girl from Ipanema?
Amane - romantic scenes in pics and movies cracks me up - unless Soki is in the same room. Then I have to deal with the OMG that's awkward to see with the kid here moment.