hmmm, add some beer bottles and other objects that they could insert into your ass with as they fuck your face. The pain and humiliation, and the rough sex that this increases can cause it to be quite a powerful experiance... Or if your a side thing at a swingers club, have the women come over with pussys full of cum.

And if you really want to go butt crazy... have them urinate on you and leave you to dry.

I like just the plain fantisy though...