I knew I was bi at a very young age. My very first sexual experience was with a buddy of mine that dared me to suck his dick. The second I had his dick in my mouth, I loved it. Even when he came in my mouth, I enjoyed swallowing it down. We had to keep it our secret, obviously, but after the first time, I was sucking his dick three or four times a week for almost 2 years. I loved it so much that I would have sucked his dick more often, if I could have.
There were times I wondered if I was gay, but I found myself sexually attracted to girls, as well.
I was very fortunate to have found a wife that was very accepting of my bi side. We entered the cuckold lifestyle, in college when I started sharing her with a buddy of mine. She wanted to see me suck his dick. He was ok with it, so during one of our threesomes, I sucked his dick while she watched. She was heavily turned on watching me do that. So, that became part of our normal play.