The Case for Anal

I’ve read plenty of blogs and this forum, leaving me with a few questions. I have never done any anal play at all and wonder what it’s really about. Why does it feel good or why is it desirable, besides the role-reversal/humbling/humiliation aspects? Also, how does one deal with the smell and possible messyness? I’ve already read the topic “Pegging”, so I’m aware of the cautions written there. Is there anything else I should know about the activity? Yep, I’m a newbie to this particular subject. Thanks.