Threesome's

All the time in college. My roomates gf used to wear a strapon and we would all fuck one another silly
 
Yes, we have played with a handful of bi guys who also wanted to suck me as well as another who was very hung and dominant and wanted us both to suck him at once.
 
Sure. Me and dude and his wife. He was a new bi guy, so I taught him a lot of things. She enjoyed partipating and watching. And she encouraged him too.
 
I have had many dozens of relationships with couples where the hub would suck me at one point or another. What is much more rare is a, mfm where the three people are equally attracted to one another. I had one very long relationship with a couple that worked this way. He was one of the rare men who totally attracted me, luckily the sexual attraction was balanced all the way around. The wife got a great deal of our attention, but she loved to help gang up on one or another of the guys too.