Perhaps this is more common as a female perspective but I'd like to know how male perspectives as well. I can basically get behind the sentiment of this video:
https://m.youtube.com/watch?v=Qg4SGWNQSAs
Rookie Scribe
Join the best erotica focused adult social network now
Login
mirrorkisses
Over 90 days ago
Straight Female, 33
United States
Forum
Rookie Scribe
I run and walk every day, eat in moderation and do yoga when I can muster up the motivation (not often enough)
Rookie Scribe
I am grateful for my ability to express myself and who I am. That may seem rather generic but self expression fills me with endless joy 
Rookie Scribe
From a female's perspective, I think that the association with the anus being more "private" is largely because women often hold more insecurity and shame in that area . I had a female friend who was afraid to have doggy style because she didn't want her boyfriend seeing her anus, as she mistakenly thought it would be a turn off for him. It really represents the ultimate vulnerability for a woman because it is seen as not glamorous, associated with a body functions that women don't wish you to know they possess lol. I believe it should be embraced as a beautiful erogenous zone, personally, as this opens a woman up to her full sexuality and I'm opposed to any form of bodily shame.