Now I envy this woman tooI can agree that I would not want to do it with another guy - if I was in a relationship with a girl.
But - in my short time (I am 22) but I knew this one girl just as a fuck buddy when I was in my freshman class who asked me and a friend of mine if we would do it with her - and we did - on 4 occasions - me and my buddy just fucking both her holes at the same time.
It was fun for me and my friend - but not something I would go out of my way to do again.
And yes - she did orgasm quite a few times when we were both in her - and we always did ejaculate into her too - which she seemed to enjoy very much - especially her "other" hole.
And yes - feeling her orgasm when I was in her vagina and my buddy in her anus felt great - but I must admit - being in her anus when she orgasmed with my buddy in her vagina was quite the experience of having my penis squeezed harder than ever!