I never knew I was bi-curious until after me and my lass had our first swinging session and everytime I recalled it, my brain was concentrating as much on his dick and the fun she was having with it as anything else. I envied her more than him.
When I spoke with him, it turned out that his experience was exactly the same. He had been captivated by the sight of his lass enjoying giving me a BJ.
He said watching her give me a BJ was more horny than her giving him one and it was her that he envied, not me. Which was exactly how I felt.