i love having my fiancee sit on my face. i eat her pussy and her ass. she grabs my head and puts more weight on her ass so that i won't stop eating her to the point i almost suffocate in it.
While I enjoy servicing a woman this way, I find that most women find this position uncomfortable and prefer being serviced orally while reclining in bed or in a comfortable chair with me kneeling between their legs.
As far as analingus is concerned, this I perform for my Wife ONLY.