This happened 8 years ago when I was 18 years old. I had gone on holiday to Florida with my girlfriend, her sister and her parents. We were staying in an apartment complex in Orlando. Toward the end of the first week, my girlfriend, her sister and mum decided that they wanted to spend a few hours shopping at a big Mall that was about 30 minutes drive away. My girlfriends dad - his name is Andrew - said that he certainly didn't want to go. This was my cue to say that I didn't want to go as I don't like shopping. My girlfriend said that it was OK, but it would mean we would have to spend our time either in the apartment or beside the pool because they would have to take the car. That was fine by us. They left us in the apartment. I went into my bedroom to change into my Speedos, and Andrew went into his to change also. I waited for him in the living room and was really surprised when he came out. He wasn't wearing the same swimming trunks that he had been using all week, and instead was wearing a white pair that were really skimpy and showed off the bulge of his cock. They actually looked real nice because Andrew was a regular at the gym and had a nice, slim body for a 39 year old. Andrew had put his hands on his hips and asked me what I thought. I told him he looked great and that I wished I had a body as toned as his. Andrew had then walked over to me and had felt the muscles on my arms and chest, commenting that I was fine and that his daughter was lucky to have me. He had then asked me to feel his arms and chest to see how the gym could really work if you were prepared to spend the time on it. I did so and enjoyed the feeling of the muscles bulging in his arms. Before I knew it, I felt his hands on my bum cheeks and he started kneading them, saying that the gym could even develop muscles there. He told me to feel his and I did so, and I enjoyed the feeling a great deal. Andrew moved closer to me and I felt the hardness of his cock that was lying to one side inside his swimming trunks. I realised also that my own cock was rock hard with excitement. Andrew just looked at me and stared into my eyes. He had then moved his head forward and started to flick at my mouth with his tongue. I was so excited that I stuck my own tongue out and we started to kiss really deeply, twisting our tongues together and rubbing each other's bums like there was no tomorrow. I am not going to go into all the details. We ended up on the unused Queen bed in his room and he taught me how to suck his big cock and lick his balls. I really enjoyed it. I couldn't believe it when he started to lick at my arsehole with his tongue and stabbing at it. He was moaning with pleasure all the time, telling me how beautiful I was and what a fantastic bum I had. We sixty-nined with him licking my arsehole and me sucking his cock. Eventually, he straddled my chest with his cock over my face, twitching his cock so that it kept hitting me on the face. He then smeared vaseline all over his cock, before kneeling further down the bed, grabbing my legs and putting a big glob of vaseline just inside my arsehole with his finger. After a while, he had his cock halfway inside me, letting me tell him to push further in and to stop when it was too painful. Then all of a sudden the rest of his cock just slid in and he was fully inside me and I could feel his pubic hair and balls pressed against my cheeks. The pain was pretty much gone. He started to fuck me gently at first and when I started to feel the waves of pleasure I told him to fuck me as hard as he wanted. He did, fucking me harder and faster, and we kissed at the same time. I was in ecstasy. He carried on for ages, stopping a few times for a brief rest to stop himself from cumming. By the time he came inside me, he was dripping with sweat. I came with a massive orgasm and had never felt so satisfied ever before. I saw my girlfriend for a while after that, but much preferred to sleep with her father who introduced me more to the world of gay sex. I still think of myself as bi, but the more time that goes by the more I think I prefer to have sex with men