I stretched my arms out above my head and stepped onto the treadmill. I cranked up the speed and an hour later I was exhausted. I had been so caught up in what I was doing that I hadn't noticed the time pass or that someone else had entered the gym.

Even though I was straight, I could appreciate that he was extremely attractive, with a great body showing through his tight-fitting t-shirt. I nodded as I walked past him on my way out of the gym.

I lifted my sticky t-shirt over my head as I stepped into the changing room. I admired my body briefly before stripping off completely, allowing my 5 inch flaccid cock to swing free. I grabbed my shower gel out of my bag and stepped into the shower, just as the man from the gym stepped into the changing rooms.

Five minutes later, the man appeared in the shower next to me. His gaze lingered at my cock just long enough for me to feel uncomfortable.

"You looked like you had a good workout," he said.

"Yeah. I didn't mean to spend an hour on the treadmill but I kind of got a bit carried away," I replied.

"I know the feeling. Dougie, by the way."

"Adam."

"How old are you Adam? Because if you don't mind me saying, you have an amazing body."

"I'm eighteen. You look in pretty good shape too."

"Thanks. I'm twenty-one," he replied.

I didn't know what to say at this point so I finished off in the shower and went to get dressed. To my surprise, Dougie followed me.

"Are you following me?" I asked.

"No," he said defensively. "I just happened to finish in the shower just after you and left my bag near where you left yours."

I looked at him sharply.

"Alright, yes I am," he said.

"Why?"

"Because I'm horny and bisexual and you're hot."

"OK, that's a bit..."

I never got around to saying 'weird' because he suddenly dropped to his knees in front of me and took my cock into his mouth and swirled his tongue around my head. He was giving such a good blow job that I forgot where I was and begun to slowly thrust my hips, like I sometimes do when me and my girlfriend are feeling particularly dirty. Dougie continued to suck my cock, occasionally licking all the way up the underside of my 9 inch hard on.

When he stopped momentarily, I remembered where I was.

"Shit! What am I doing?" I shouted, removing my cock from Dougie's mouth. "What the hell are you doing? I've got a girlfriend!"

"You can't deny it Adam, you loved it. Besides, your girlfriend doesn't have to know."

"I've got to go," I said.

"No you don't. You know you want to stay."

I didn't know what to do. Everything he was saying was completely true. Was I gay? I couldn't be, I loved fucking my girlfriend and having one night stands. I'd kept sexual relationships from my girlfriend before so that shouldn't be the problem.

"Fuck it," I muttered.

"I'm glad to hear it. Now, down on your knees."

"No way! I am not going to be a submissive."

"Well that could be an issue because I'm always the dominant."

"That's going to have to change. We'll need to be on a level playing field. Now, I choose to get down on my knees and suck your cock, just like you chose to give me a blow job, alright?"

"Fine," Dougie replied.

Slowly, I knelt down, trailing my tongue down his perfect body and I realised: this was love. Not what I had with my girlfriend.

I didn't truly love her, otherwise I would be completely and utterly devoted to her. I wouldn't be having one night stands with girls whose names I couldn't remember the next day.

Eventually, I reached Dougie's cock. I hadn't realised until now that it was almost as big as mine, maybe 6.5 inches at half mast. Thinking about what I would want done to my own cock, I went down on him, tickling the tip of his penis with my tongue. He groaned.

"That is so good, Adam."

I licked my way down his elongating shaft and took one of his balls into my mouth. I sucked on it, and then moved onto the other.

"Just get on with it, Adam," Dougie moaned.

I opened my mouth, and slid it over his circumcised head and down his shaft until 5 of his 8 inches were in my mouth. I hollowed my cheeks and sucked on him as hard as I could, not really knowing what I was doing. It wasn't long until he threw back his head and let out a cry. Instinctively, I pulled his cock out of my mouth and began sucking on his balls. He grunted a few times and with a loud moan, he blasted out seven jets of cum.

"That," he panted, "was the best blow job I've ever had."

"Can I fuck you?" I asked him.

"Of course. What position do you want?"

"I want to look at you while I do it."

"OK."

He took a bottle of lube out of his bag and applied it to his asshole.

"Are you clean?" he asked

"I don't know," I replied, "My girlfriend has refused to have sex with me without a condom, so I never bothered to find out."

Dougie nodded and got a condom out of his bag.

"Here," he said, "just to be on the safe side."

I took it off him and put it on my cock. He lay back on the bench with his legs in the air, inviting me into his ass. I pulled his cheeks apart and slid my cock in slowly, until it was buried to the hilt.

"Fuck me hard," Dougie whispered sexually. "I don't give a shit whether it hurts or not."

Having been invited to fuck him hard, I began pounding his ass, my balls slapping against his ass with every thrust, which also elicited a grunt from Dougie.

"You're a noisy one, aren't you?" I whispered, before shoving my tongue in his mouth and kissing him as hard as I was fucking him. Still grunting, he kissed me back and gripped my ass cheeks. Slowly, he wriggled his middle finger into my asshole. Now it was my time to groan.

"That feels so good," I whispered.

Dougie began to move his finger in and out of my ass. His finger-fucking made me break off the kiss, and speed up my own fucking as I neared climax. I began to groan and grunt louder than I ever had with a girl and Dougie almost had to shout to make himself heard over the top of the sounds.

"I want you to cum on me," he said.

I nodded and sped up my fucking, getting ever closer to orgasm. As I felt I was about to explode, I pulled out of his ass and removed the condom, just in time to shower him with the biggest cumshot I've ever unleashed, during my best ever orgasm.

After we'd recovered from our intense fucking session, we looked at each other and grinned, shocked at how messy we were, covered in my cum. He licked off my chest and swallowed it laughing. We headed off to the shower to clean up... again.

After we were clean and dressed, we exchanged mobile numbers, promising to meet up and do it again sometime.