3-person living arrangements.
Once, for a period of several weeks, while I was in a transitional time of my life, I shared living space with two other persons, a single woman and a single man. We each had our own bedrooms, but share the other spaces.
The woman and the other man had been sexually involved before I came on the scene, so I was surprised when the other man asked if I would like to be included. The first time, the woman came to my room and we had sex together, then she went to the other man's room and they did the same.
Later, the other man wanted to talk with me about the experience, and get my reactions to what had happened. I was surprised to learn that I could discuss it so easily with this "other man".
During the few weeks that we were all together, she usually came to my room first, then to his, but a few times she reversed her pattern. And, one time only, we were all three in the room while she had sex with us both in turn.
Have any others had similar experiences?