Hi,I understand in the mood like if you want or not depending the situation, is that right? If correct I think is the cleverst opinion I have never read about anal sex.Sometimes you want it some others dont.I have experienced that manytimes,and I have a lot of anal experience.
We did it that when when young not to get pregnated, and when you have done 3 or 4 times your ass get used and there is not pain at all.
I consider my ass as my vagina,they work the same, but to start with anal orgasms I need first 1 or 2 from my vagina, after that my ass get as soft and open as my vagina and I have exactly the same feeling in one or the other.Sometimes is hard to distingue where is it.
Against pain first timers some people say is only on their minds, I dont think so,there is a muscle and you have to learn to relax it and is best to train alone before getting a real cock.
About lidocaine,I dont recomend is not safe,if there is not feeling you can get hurt.There is a special thing very used in Argentina, they call it xilocodeina or similar, now is forbidden in spain,just few drops make posible total dilatation of the anus, more than you can imagine.I tried and was amazing, but no more in spain.
For me , just to feel my juice running down my ass while getting fucked in vagina,make me orgasm and my ass start to get hungry.About farting, depending on the cock, I fart the same anal or vaginal.