Never my wife was fucked anally (yes I did).
However, during several hot encounters she had thoughts that would happen.
In our (written) fantasies she had a lover who demanded that he be given the privilege over the gap between her buttocks.
She had to promise him that she would never allow me to do that again.
In that fantasy, she did just that.
She once wrote back to me, "It would be even hornier if he orders you to put his dick in my ass hole. I would find that even more exciting."