Shown Up

"Mmm, love that deer in the headlights look," she said, not even a hint of sarcasm in her voice. She flipped through the ones of me bent over the dresser. She had been right: the tennis skirt was very flattering and showed off my ass nicely. I was surprised at how natural the sultry expression looked on my face in that picture and the kneeling ones. It was amazing how delicate and vulnerable I looked in the photos on the bed, but the way my mouth hung open suggested an openness that was frankly arousing.

Finally, we got to the ones Amy took of me and Sarah. I looked tiny and scrawny next to her bulky, powerful form, and my nervous expression gave me an added air of vulnerability. Each of her thighs was nearly as thick around as my waist. However, there was no mistaking the affection from me, and the lascivious look on Sarah's face in the last picture of me leaning into her and kissing her cheek while she grabbed my ass.

"So, what do you think?" she asked.

"I... They came out pretty well." I was blushing because I knew it was true. There was something mesmerizing about the contrast between Sarah's strength and my weakness in the last pictures.

"Agreed. We look good together."

Sarah reached down and put her hand on my cheek, slowly caressing it until her fingers were just under my jaw.

"Your heart's beating so fast right now. You're trembling too." Sarah observed.

"I-It's just not what I expected on my first day at the gym."

"Well," she said, letting go of me, "I know what'll help you calm down."

She turned and walked over to the dresser again. I was mesmerized watching her thick thighs as she took those few steps, then by the well-defined shape of her hamstrings as she bent over to rummage through a drawer. She pulled something out, set it on the dresser in front of her, then slipped down the gym shorts, revealing her bare ass. Now I really couldn't help but stare, watching the muscles of her legs and the gyration of her ass as she stepped into a harness. It didn't even occur to me to think about what she was doing until she turned around, revealing the six-inch black strapon she was wearing, glistening with lube.

My mouth hung open as she walked by me, brushing a hand over my dainty shoulder as she stepped behind me. Her hands ran down my back and sides, feeling up my slender body. Her breath was hot on the back of my neck and her lips brushed my ear.

"Girly boys like you are a guilty pleasure of mine," she whispered, making my hairs stand on end. Suddenly, I felt a swift slap on my ass, and she was gone. The mattress groaned behind me, and I turned to see Sarah sitting on it, looking intently at me. She slid back further onto the bed until she was sitting with her legs flat on the bed, propping herself up with her hands, the strapon sticking up.

"Come here." She commanded, beckoning me over with her finger. My breath caught in my throat as I stared at her nervously.

"I-I don't know. That's not really my thing." I stammered.

"Bullshit. You're a terrible liar." She wiggled her hips a little. "I know you want it."

I looked her up and down, admiring the bulging shoulders and thick triceps propping her up, and the massive, shapely legs lying flat on the bed, and her cleavage visible in the tank top she was still wearing. I remembered how it felt to be pressed against her, how her muscles had felt under my delicate hands and against my torso when I had leaned into her.

Sarah had called my bluff. I really did want to give in to her, to submit to this beast of a woman. I took a step forward. She grinned and patted her thigh invitingly. Slowly, trembling with nervousness and excitement, I climbed onto the bed and slung my leg over her, straddling her muscular thighs with my slender ones. Kneeling, I inched forward toward the strapon. Sarah reached up and grabbed the back of my head gently, leaning up and pulling me in closer.

Our lips met in a warm kiss, and it wasn't long before I felt her tongue slip into my mouth. I placed my hand on her shoulder for stability and leaned in, feeling the strapon rub against my dick through the skirt and panties. After a few seconds, she slid her tongue out of my mouth and smiled, then started to lean back and lie down on the bed. She put her hands on my hips.

"Alright, kneel up a little and inch forward."

I obeyed, and soon she was running a hand under the skirt, pulling the panties to the side. Soon, I felt the tip of the strapon teasing one of my cheeks. She had a firm grip on my hips now, guiding me onto the strapon.

"Ease down onto it."

I slowly lowered my body, feeling the strapon part my cheeks. Soon, I felt the tip stretching me and pressing into me. I gasped a little in shock. Sarah smiled up at me warmly.

"There you go, nice and slow."

"Oh!" I gasped again, feeling it deeper and deeper inside me. It was painful, but not excruciatingly so, despite the lube, but Sarah's firm grip on my hips held back my natural instinct to try to climb off it. I could feel it stretching me out and filling me up until I eventually felt Sarah's skin against the skin of my ass cheek. She felt sturdy underneath me, and I realized I was resting on her hips. The strapon was all the way in.

"Good girl," she purred, making my cheeks flush hot. Eager to please, I knelt up a bit, sliding up the strapon before easing back down. Sarah grinned up at me and exhaled.

"You're a natural at this too," she said, sliding one of her hands back to grab my ass. I gasped and then giggled, sliding up and down the strapon again. Now that I'd taken the strapon all the way in, the pain wasn't as sharp, and I enjoyed watching the pleasure on Sarah's face as I bounced. She held her hips in place as I eased up and down the strapon, feeling totally solid beneath me.

I looked over and saw us in the full-length mirror, my slight form straddling the muscular woman. I arched my back and began to bounce faster on the strapon, grinding back and forth, amazed at how feminine I looked in the skimpy outfit as I rode Sarah. Her fingers dug into my hips and pulled me down onto the strapon, suddenly filling me deeper than it had before.

"Oh! Sarah!" I gasped sharply and loudly, overwhelmed by the pleasure. Suddenly I was overcome with a wave of self-consciousness and went still.

"Something wrong?" asked Sarah, sliding a hand off my hip to take my hand.

"Do you think Amy overheard that?"

Sarah giggled and then smiled warmly and reassuringly, stroking the back of my hand with her thumb. "So what if she did? You think she doesn't already know what we're doing in here?"

I glanced in the mirror and saw my face had turned bright red. Suddenly, Sarah bucked her hips, thrusting the strapon up into me. I gasped in shock.

"I upstage some shy, pretty boy in the gym."

She thrust up again.

"I bring him home."

Another thrust.

"I dress him up in a skirt and lingerie."

Thrust.

"She knows I'm going to make you my bitch."

The hardest thrust yet sent a wave of pleasure through my whole trembling body, forcing an excited squeal out of me. She grinned at the effect that thrust had on me and gripped my hips tightly, holding me in place while she began driving her hips up hard. She tilted her head back in pleasure and closed her eyes as she pounded me furiously, each thrust like a hammer blow deep inside me, sending shockwaves through me. I moaned helplessly as I looked into the mirror and saw her bouncing me on her lap like I weighed nothing at all, my delicate figure easily lifted by her powerful glutes. I had always known she was strong, but now I was feeling her full power, and it was incredible.

My calves cramped and my breathing was heavy as an orgasm filled my whole body. I'd never felt this kind of pleasure before and closed my eyes, letting her powerful thrusts become my whole world, totally filling me up. After who knows how long, my eyelids finally fluttered open to see Sarah smiling up at me, breathing a little heavily from exertion. I felt another small, playful little thrust, and it occurred to me she hadn't finished yet.

Still in the afterglow of the orgasm and seeing that statuesque body beneath me, I felt an overwhelming need to please her, to win her approval. I began to bounce on the strapon again, and Sarah let out a little exhalation of pleasure. Letting her vocalizations be my guide, I found the exact angle that was doing the most for her and stuck with it, slowly increasing the rhythm of my bounces. Her grip on my hips relaxed and she closed her eyes, tilting her head back and moaning, letting me take the lead. I watched myself ride her in the mirror, once again enjoying how dainty and feminine I looked atop her powerful body.

"Oh! Oh! Casey!" Sarah moaned. I rode harder and harder, and soon her grip on my hips tightened once more as she pushed up hard into me again, moaning ecstatically. I could feel her trembling in pleasure and after a few frantic thrusts, she lay back contentedly, breathing hard.

Slowly, I eased off the strapon. My legs were sore, not to mention my ass, but I felt I was glowing nonetheless. Suddenly aware of the mess I had made in the panties and skirt, I got up and limped into the bathroom to clean up. The panties would definitely have to be washed, but I found the skirt was still fine, and when I opened the door back into the bedroom, I found Sarah standing in the way.

She immediately pulled me up against her, holding me in a tight embrace, and kissed me deeply, sliding her tongue into my mouth. I felt warm and safe in her embrace and enjoyed the moment, pressed up tight against that rock-solid body. Soon after I closed my eyes, I felt a playful squeeze on my ass and giggled.

"See? I told you that would help you relax," said Sarah with a warm smile.

I nodded and stumbled back to the bed, exhausted. I thought the workout had kicked my ass, but sex with Sarah had been even more arduous. As I knelt on the bed, I saw myself in the mirror, panting, my hair disheveled, with a thin sheen of sweat over my body. Sarah placed her hand possessively on my shoulder, and I could see a lusty look in her eyes in the reflection.

I was her girl now. And that was the most satisfying feeling in the world.