I struggled not to run home from school. It would arrive and day now and just the thought caused my heartbeat to quicken. Typically I got the mail before my mother, so I was not too concerned that she might discover it. If she did, I had a good excuse prepared, a reaction which I had practiced many times, for why an 18-year old boy would receive such a thing.

As I approached our large gated home I saw that her car was not in the driveway. I saw, too, that the mailbox was full. And peeking out the top was the object of my desire: a JC Penny catalogue addressed to me. I grinned and could not help but run the remaining distance. Eagerly I examined the cover, which showcased a sexy woman in a bikini. She was hot, but not the one I wanted to see. There was one model in particular that I planned to jack off to, a woman named Robin. She was by far the sexiest in the catalogue. I grinned in anticipation and headed inside.

Immediately I dropped my stuff and headed for the couch. It would have been smarter to go up to my room but I simply could not wait. I had to see what Robin was wearing for me this time. If my mother came home I would hear her pull up and have plenty of time to run upstairs.

I laid on my back and pushed my shorts and briefs down around my thighs. My cock sprung free, arcing upwards but not too hard yet. I opened the catalogue and quickly leafed through the first several pages, which were dedicated to swimwear. Robin may have been there but I did not care for swimwear. What really turned me on was underwear, bras and panties. I flipped rapidly through the catalogue until I finally came to the women’s underwear section. And it was there that I found what I was looking for.

She was wearing a sky blue lace thong with matching bra. Her ass was facing the camera with her body twisted, showing the side of her breast. She smiled seductively, her lush brown hair spilling down over her shoulders. I began to rub myself with the catalogue propped up beside me, my eyes gazing at that perfect ass. The thong was just a triangle above the crack of her buttocks and then the material disappeared between her cheeks. So essentially I was staring at her bare bottom. My cock swelled and I squeezed it hard.

I started masturbating furiously, staring into Robin’s eyes, imaging that her sexy smile was just for me. I thought about spanking her, about pulling her panties off and fucking her savagely in the ass. Recently my thoughts about Robin had become naughtier. I used to just look at her body and jerk off. Now I tended to entertain fantasies about fucking her, rocking her back and forth on my rock-hard shaft. My lust was growing with each catalogue and I worried that it would soon get me into trouble. I wanted her so badly that I had not even been able to wait to get upstairs. If my mom came home at the wrong time, it could become my worst nightmare.

But now was not the time to think about that. I continued instead to think about fucking Robin in her ass, digging my cock deep inside, piercing her body. When I grew tired of that I flipped the pages until I came to her next photo. Now she was wearing boyshorts, which are somewhere between shorts and panties. They were purple and yellow with an elastic waistband and fabric that just barely covered her ass. She was facing the camera, still with that same seductive smile, and I was thrilled to see that she had no top on. Her arm was covering her breasts, but the curve of one of them could still be seen. I moaned softly, thinking about pushing her hand away and sucking on that tit. It was large and inviting, a generous C cup which was just asking to be rubbed and sucked. I would push her onto her back, slide her boyshorts down, and fuck her hard as I licked her breasts. I closed my eyes in pleasure, only to open them again to refresh the image of her sexy thighs and tummy, and that tantalizing breast.

I kept flipping through the pages, growing harder and harder as I found more and more pictures of Robin in sexy lingerie. Then I gasped when I discovered a full-page image of her towards the end of the catalogue. It was a frontal shot, her body angled slightly to the side. Her supple breasts were supported by a tiny purple lace bra and her legs were spread, showing just a small patch of panties covering her pussy. Her outfit was mostly strings, and it was the hottest bra and panties I had yet to see her wear. The sexiness was magnified by the way she was gazing into the camera, with her head bent forward, eyes up. I was convinced that expression was inviting me in for a fuck. I had no problem imaging her naked, for the bra and panties left little to the imagination.

Holy shit, I thought, this is more like porn than an ad. I rubbed and squeezed my cock, pretending it was deep within her, that my hand was her muscles contracting around me. I felt myself building to a climax, masturbating hard and fast. Desperately I reached out for the catalogue and pulled it close, rubbing my shaft against her almost bare breasts and against the tiny panties between her legs.

Just as I felt the cum welling up inside my cock, ready to explode, I heard a car pull into the driveway. My mother was home. But I was just too turned on. Instead of stopping like any other rational boy would, I masturbated harder, tearing the page as I ground the image of Robin’s body into my shaft. I heard my mom close her car door and still I did not stop. I felt myself about to cum, panting heavily, sweating, incredibly turned on by the stringy bra and panties and thoughts of stripping them off. It was not until my mother was actually climbing the steps to our door that I finally came. She would have to pass through the kitchen before she could see me, and so I let the cum flow, shooting it all over Robin and my belly, moaning loudly. I came and came, even as my mom opened the door. She was inside the house, only one room away, and here I was with my cock out and cum all over myself and the catalogue.

I quickly tossed the sticky pages under the couch as my mother’s footsteps began to cross the kitchen. Yet I still had my shorts down and was covered with cum. She would see me in seconds! Desperately I pulled my shirt down over my body, letting it soak up the thick liquid. I then pulled up my shorts as I turned to face the back of the couch, with my mom only one step away. My bare ass was visible for a moment as I turned, but then it was covered. I froze, feigning sleep. I could not know if she had seen me as I pulled up my shorts, if she had seen my bare ass. There was silence for a bit, and then I heard her head into the bathroom.

***

The rest of that day passed uneventfully. I managed to retrieve the catalogue and hide it in my room. The following morning was a Saturday and I heard a familiar noise as I awoke. My mom was working out down in the living room. She worked out almost every day but the weekend was the only time I was home to see it. I crept quietly out into the hallway to take a peek. Our home was actually sort of a mansion which my father had purchased before he died. And so from the balcony I had a bird’s eye view of the living room. And down there was Robin, the model from the JC Penny catalogue — my mother.

I used to feel weird about it, but those emotions were now few and far between. I had almost become comfortable with the fact that I was sexually attracted to my mom. I liked to think that it was not really my fault. Surely no one could blame me for being turned on by such a hot woman. My reasoning was reinforced as I gazed down the stairs.

Like most mornings around eight, she was exercising, following one of her many videos. And, like always, she was doing it in what she had worn to bed the night before. This morning it was a red nightie that just barely covered her ass. Constantly the nightie would ride up, revealing her pink cotton panties underneath. Her back was to me, but I knew that nightie, and I knew it did not support her breasts well. They were likely spilling out as she moved.

It was pretty inappropriate for my mom to work out in such clothing, and it used to piss me off. I guess she was just comfortable with her body — understandable, given how amazing it was, and necessary, given her profession. However, for the longest time I was really annoyed by it…until I hit puberty. Since then it had just been a massive turn-on.

She turned to the side and I saw that her breasts were in fact barely contained by the nightie. My cock responded as she got down on her hands and knees, giving me a great view of her cleavage. Her nightie slid up around her hips when she lowered her head down to the floor. She was doing yoga, I realized with growing excitement. Her ass stuck up in the air, the nightie falling down around her head. She lifted it back a little so she could still see the video. The undersides of her breasts were in plain sight, so far had her nightie fallen. I gazed longingly at them, and then down length of her back. My eyes locked on the curve of her ass, only a small portion of which was covered by her panties. She wasn’t wearing a thong, but it was close. I could see my mother’s profile and if she looked my way she would see me leering at her. But she would not, for her attention was focused on the exercise and the TV.

I was lying on my stomach and began to grind my cock against the floor as I watched my mother work out. She rolled her body up and arched her back, leaning on her hands, her nightie still bunched up at her breasts. I almost moaned at the sight of my mother’s clenched ass and arched back. I continued to watch her gyrate and stretch until I just could not stand it anymore. I slid my hand under my body and began to stroke my cock.

She stood, only to bend down again in an upside-down V, with her hands and head touching the floor and her ass up in the air to make the tip of the V. She was facing directly away from me now, and I could see the lips of her pussy below her ass. Beyond that was the underside of her breasts. She bent a little further, revealing more of her breasts. Her nightie had almost slid completely off, and her amazing tits were on the verge of hanging free. My cock surged when I saw a hint of her nipples, and I gasped in pleasure. I had often gotten near-glimpses of my mom’s nipples, and oh, how I wanted to suck them. I entertained numerous filthy thoughts about those breasts, including rubbing my cock between their silky smoothness. That was just too much for me. I came then, a long, hard orgasm that filled my shorts. All the while I imagined I was cumming over her breasts. After that I retired back into my room.

***

A few hours later I awoke to my mother’s soft touch. She was sitting on the edge of my bed, wearing tight jeans and a snug t-shirt. The shirt was pretty short, allowing me to see her midriff and, in the back, the waistband of her white panties. It was like a position from one of her modeling shots, only now, she was in my bed. Her hand squeezed my shoulder.

“Babe?” I was already erect, but her whisper made me even harder.

“Hey,” I replied groggily. My eyes locked on her panties.

“I made you breakfast. C’mon, it’s past eleven.” I nodded and watched her ass as she left my room. Sitting up in bed, I realized that I was far too erect to go downstairs. I waited a while for the erection to subside, then headed down in my shorts and t-shirt. The water was running in the kitchen. She was washing dishes, leaning over the sink, the waistband of her panties still visible. I came up behind her and kissed her on the cheek. My crotch briefly pressed against her ass, and I took in a sharp breath. I had been doing things like that more and more lately. Any chance I got, I rubbed against, kissed or hugged my mother. She didn’t seem to notice — or maybe she didn’t mind. Was it possible she enjoyed it? No, that was doubtful.

I pulled away from her and sat down to eat my breakfast. She flashed me a smile in response to my kiss, then resumed washing up. I enjoyed a wonderful view of her ass as I ate. It swayed seductively, moving with each motion of her arms. My cock began to grow hard beneath the kitchen table. A vision formed in my head of those jeans being pulled very slowly down her hips, reveal her bare thighs and buttocks. I thought about the view I had been blessed with this morning: my mother’s smooth ass and generous tits. My eyes glossed over as I become lost in the rhythm of her butt.

When she finished with the dishes, she turned to face me. My eyes moved up to meet hers, and I had the feeling that she knew I had been staring at her. Embarrassed, I averted my eyes back down to my food. We made some small talk and then she went out to do errands. As soon as she was gone, I promptly went back upstairs to masturbate.

***

The next morning, which was Sunday, I was again woken by my mom. She was sitting on my bed, but closer this time, with the back of her ass pressed against the side of my leg. A hand was draped across my other leg. She was wearing only a tight pair of white boyshorts and a tank-top.

“Morning babe,” she whispered.

“Mmph,” I mumbled. Glancing at the clock, I saw it was only seven thirty — far too early for a Sunday. “What?”

“I want you to work out this morning,” she said. “You need it. You just don’t get enough exercise.”

I sighed, but I knew better than to argue with her when she used that tone. “Alright mom.”

She smiled. “Ok, great. Let’s go.”

I followed her downstairs and was taken aback when I realized just how skimpy her clothing was. Her white bottoms and tank-top were both pretty thin. I could see the curve of her well-sculpted ass through the bottoms. I felt a little bit of that old annoyance. God, why did she have to dress like that around me? Other mothers didn’t act like this. It was just so damned inappropriate.

I followed her towards the TV. assuming we would do cardio, but she walked past it. She was heading to the room in the back of the house that served as a personal gym. Ugh, I thought, she’s going to try and make me start doing weights. She had tried numerous times to get me on a weight-lifting regiment. She herself used light weights for toning, but she had surprised me one day with some heavier weights. I had not been enthused. I was fairly fit already and did not believe there was any need for me to build muscles.

“Aw great, again with the weights? You know I hate this.”

She glared at me out of the corner of her eye. “It’s good for you, hon. Even just a little.”

I decided to resign myself to it. It would be far easier to go along with her plan for a little while than to get into an argument. When we entered the gym, the sun was shining brightly throughout the room. The bright light made her boyshorts and top even sheerer. Her top was actually transparent now. I tried not to look at it, because this was certainly not the time to be getting an erection.

My mom picked up a dumbbell and sat on the end of one of the benches. She straddled the bench, leaving a little bit of room, and patted the spot in front of her. “Sit here, babe.” I paused. Before me sat an underwear model who also happened to be my mother. Her flowing brown hair spilled down over her back and shoulders. The shape of her breasts was clearly visible, as were here prominent nipples. And her legs were spread for me, even though all she had on was thin underwear.

I sat as instructed. She was very close behind me but we were not touching. My mom passed the dumbbell around my body and I took it, awaiting her instruction. She explained that I was to spread my legs and rest my elbow against the inside of my thigh. I did so. I then followed her next instruction to move my arm a certain way.

“No hon,” she said. “Not like that. It’s like…here.” She scooted forward on the bench. Her bare thighs touched either side of my ass and I felt her breath on my neck as she leaned forward. First she grabbed my elbow and slid it further up my thigh. Her hand slid with it, pushing my shorts up a little, her warm fingers brushing against my skin. I shivered and my cock got very hard very fast. “And the motion is like this.” My mom took my hand and lowered it. She had to move closer to me in order to lower it all the way down and her supple breasts pushed against my back. I felt her crotch touch the back of my ass as well. When she lifted my hand back up I thought she would pull away, but she did not.

“You do it like that, babe.” I nodded but could barely concentrate. Her thighs were wrapped around me and her hands were now resting on my hips. Her breasts, too, were still touching my back. My breath quickened. She had been this intimate with me in previous sessions so I didn’t think the sexual contact was intentional. I was her baby boy and thus such thoughts probably did not even enter her mind. For me, it was a different matter.

Once I had the motion down she pulled away and stood. As she crossed the room, she told me how many repetitions to do and that I should do both arms. It was difficult to pay attention with the sight of her sexy body in front of me. It became even harder when she draped herself across the leg-curl machine. She was lying on her stomach, angled a little so that I could see the length of her body as well as her amazing ass. Her breasts bulged out on either side. I was mesmerized as she worked her legs, bending them up into the air and then straight back out, over and over, moving her well-toned muscles. I could not stand it.

I put the dumbbell down and approached her. My cock created quite a large tent in my shorts, so I approached from behind, where she could not see me. I knelt down and she turned, smiling. Then I did something daring: I reached my hand out and wrapped my fingers over the back of her thigh. She jumped, but did not stop working. I felt the muscles moving in her thigh. It felt incredible.

“So is this the muscle you’re doing now, mom?” She nodded. I took another dare, and briefly touched her ass for one of her leg motions. “I don’t feel it here though.”

“Mmm. Yeah babe, it only works the lower hamstrings.” She smiled at me. “You’re taking an interest, that’s great.” I shrugged and continued to watch her move. Soon she stopped and got up. “Okay, now you do it.”

“Okay, mom.” I climbed onto the machine, remaining hunched to hide my enormous erection. It felt good pressing my cock against the padding, which was still warm from my mother’s body. She guided my legs under the mechanism, her hands touching my calves. Once I began the exercise her hands slid up to my thighs. I gasped a little and stretched my arms out over my head, causing my shirt to pull up over my lower back. Her hands felt so good. I ground my hips down while working my legs.

“Hmm,” she mused. “Your legs feel pretty tense.” Her hands were rubbing my thighs. “You want a massage, babe?” My jaw dropped. A massage? From my mother, who was in her panties and a see-through top? It was a dream come true. She had given me massages before, but only when I was much younger. Before I had become attracted to her.

“Yeah,” I managed to get out. “If you think I need it.”

“Ohh, I really do.” She moved up beside me. The bench was thigh-high for her. “You just relax.” And then her fingers began to dig into my thighs, kneading the muscles. Her hands roamed up and down my legs. I was breathing heavily and moving my hips every so often, hoping she did not realize my arousal. She rubbed up my back, to my shoulders, which she massaged hard. Her breasts bumped softly against me as she leaned over my body. “You’re really tense, hon,” my mom said. She was breathing heavily too, but from physical exertion.

I moved my hips more, grunting with each breath. She continued to rub and touch me as I worked my cock towards a climax. It was becoming more obvious that I was grinding my hips but I found I could not stop myself. And my mother did not stop, either. If anything, she unknowingly encouraged me by getting more into the massage herself. I heard her panting behind me.

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