Hmmm I'm not sure I understand your question, but I can tell you that after the waves of pleasure I feel as I'm cumming subside my ass feels completely relaxed and can take a fist quite easily.  I personally don't like to do this because it makes me feel over stimulated and takes away from the after glow of the orgasm.  I also like the person fisting me to remove their hand right as I orgasm.  It is painful to me when I orgasm and the person fisting me continues to stroke in and out or tries to move their hand inside me as my ass contracts and squeezes down on their hand during my orgasm.  After these contractions subside my ass totally relaxes, but as I said I personally feel over stimulated if my ass is played with at this point.  I hope this answers your question.

also Thanks for every ones comments.  They are much appreciated.  : )

It's not only you that feels like that.  I would say that is pretty much the same for me too.  I just used to many words to try and say what you just did here.  lol  : )