I lifted the towel to my face, wiping off the sweat that had accumulated as I paced on the treadmill.

Music filled my ears from the CD walkman I carried as I neared the end of my workout. I had come to the gym more than an hour before, had already lifted weights for a while, and was almost done with my cardio exercise.

As I lowered the towel, I looked to my left and right, and noticed that the row of treadmills was empty except for mine. I glanced down to the weightlifting area on the first floor, and saw more of the same.

Puzzled, I turned and looked at the clock on the wall behind me.

"Oh, shit," I exclaimed, as I realized what time it was. It was 6:15, and the gym had closed 15 minutes earlier. I didn't notice the closing – the crowd had been light because it was a Sunday evening.

I stopped the treadmill and gathered my things, then headed downstairs towards the locker room. I stopped off at the exercise mats at the base of the staircase to do some quick post-workout stretching, leaning against the wall as I lifted my leg behind me to stretch out my quads.

"Oh, hey Jon," I heard behind me. I turned my head and saw Jennifer, the gym attendant, walking up behind me.

"You looked so serious up there on the treadmill, I didn't think I should bother you," she said with a chuckle. "But I made everybody else leave at the regular time."

I smiled back at her. "Thanks," I said, "I appreciate it. Listen, I'm going to go hit the shower real quick and then I'll be out of your way."

"No problem," she replied. "I've got to count down the cash register from the juice bar anyway, so I'll be a little while. Plus, I was going to stick around and work out after I lock up anyway."

She turned and walked back towards the gym office, and I headed for the locker room. Once there, I slipped off my sweaty workout clothes and went into the showers. I turned on the faucet, rinsed off, and lathered up.

As I stood under the warm stream of water, I started thinking of Jennifer once more. I had eyed her for a while, checking out her lean, muscular frame, her shoulder-length brown hair, and her ample bosom, every time I came to the gym. A couple of weeks earlier, I had gotten up the courage to ask her out, and she accepted. We had gone out to dinner and gone dancing a couple of times, but it hadn't gotten very physical yet.

After our last date, we had shared a good night kiss that turned into a short make-out session at the front door of her apartment. But we didn't want to rush things too much, and it ended there – and I was left wondering when we would take it to the next level.

I turned off the water, and stepped out of the shower, drying off with my towel. I walked out of the shower room and into the locker area, brushing my hair dry as I headed for my locker. Knowing I had the men's locker room all to myself, I made no effort to cover my semi-erect cock as I walked through the room.

I finished drying off, and sat down to slip on a clean pair of white tube socks, which I bunched up around my ankles rather than pulling them all the way up to my calves. I flexed my feet and curled my toes up inside the dry socks as I got my black Jockey boxer briefs out of the gym bag. I stepped into the underwear, pulling them up as I arranged my package – and heard someone clear their throat behind me.

I spun around, and Jennifer was standing there, her arms crossed over her chest. She had a smirk on her face and a devious twinkle in her light blue eyes.

"Mmm hmmm, not bad," she said, as my face flushed red. Her eyes roamed over my six-foot-tall, 200-pound body.

"What did you see?" I asked.

"Something I like," she replied, then walked over and threw her arms around my bare shoulders, planting a kiss on my lips. As we kissed each other deeply, our tongues roaming in each others' mouths, her hands ran along my clean body. She ran her fingers through my curly brown hair and tickled my goatee, and her hands swept over my hairy chest, squeezed my tight bicep, grabbed my butt. One of her hands dropped to my crotch, grabbing my hardening erection.

"MMM HMMMM," Jennifer moaned into my mouth, as she squeezed my hard cock through the soft cotton of my boxer briefs. She pushed on my chest, forcing me down onto the bench in front of her. She slipped her tennis shoes off, revealing her tight white ankle socks with gray heels and toes, and then pulled her black golf shirt with the gym logo over her head.

She pushed her loose workout pants down from her hips and stepped out of them, leaving her standing there in socks, a pair of gray lycra workout shorts and a matching sports bra.

Jennifer stepped up to me, kneeling slightly as she pressed my face up to her D-cup breasts, then lowered...