i did the 3-some thing both ways. no...not in a gay way either.
when i was 20, i was living with a 30 year old(always liked them older women

). anyway, i used to visit her at work quite often. one of her co-workers paid me some compliments...she was telling my girl these things. well one thing led to another and whalla...2 slightly drunk older women who want me. it was weird at first though. kinda like losing your virginity all over again. after a few years of having only 1 ass, 1 pussy, and 2 boobies in bed with you, suddenly everything is doubled

! who do you grab first...and where? needles to say it all worked out fine till i got just a wee bit jealous that the other chick really wanted my girl....yep, she was a lezbo. but at that point i didnt give a fuck...i was doing the lezbo doggie style while she caressed my girls boobs and was making out with her. ok, so she was a bi-sexual not a lezbo. either way, i was getting 2 good looking older women at once(patting myself on the back).
the other way, well a guy i used to work with...he was cool and all so we hung out sometimes. sometimes his wife would meet us. seems like she had mentioned something to him about me, he was up for the experience, and asked me to join in the fun. his wife, while only 3 years older then me( a bit young but i got over it) looked good, so i figured why not. after setting some rules, namely no homo shit which was a given by both us guys, we got to it. it was all supposed to be for her pleasure. and i guess it was because i got invited back a couple more times. and no...IT NEVER TURNED HOMO! NEVER EVER EVER

.
i guess i'm lucky because both were good experiences. no drama. no one got hurt. no one(me) got molested. its definately something i'll remember...because it really was a good experience. just like when i lost my virginity in a whore house...but thats for another time.
so i guess anything goes as long as everyone acts kind of adult like and no one crosses the line. when the rules are set, and everyone follows them it could, and will be, a very nice and interesting moment that you'll look back on and not be embarassed about.
have a nice day