It had been a little bit of harmless fun to begin with. I’d noticed my son, Toby, starting to pay attention to my body and just played along. Nothing gross, just leaning over a little deeper than strictly necessary when serving his food, or sometimes bending at the waist rather than at the knees.

It was at about the same time that he took to doing his homework lying on the lounge floor, neither directly facing the TV or me, but a little of both. I’d smile to myself as I crossed my legs, showing him a little thigh, and his eyes would be there in a flash. He was going through puberty, and he was curious; that was all. I’d never been accused of being a prude, and if he wanted to look, I didn’t mind showing him. Just a little, anyway. Besides, I’d worked hard to keep my body in shape, jogging and swimming, and I liked to wear sexy clothes. Nothing sluttish, but nothing I’d wear to church either. If I went to church. Which I don’t. I honestly don’t recall ever thinking about what effect my displays might be having on a pubescent boy’s penis, or what he might do with those remembered images, alone in his room at night. At least, I don’t think I did.

I do admit that I had conflicting emotions when I first saw that I’d given him an erection. And I chastised myself after I found myself thinking, proudly, that it was a very respectable size for a fourteen-year-old boy. And yes, if you really must know, I did feel a little tingle in that part of my anatomy most fond of doing exactly that.

I hadn’t been entirely celibate since Daniel, my ex and his father, decided first to cheat on me with the young sales rep from his Florida branch, and then to leave us to go live with her. But I’d been careful not to expose Toby too much to either the men or women that I’d had liaisons with since then. And yes, I was, and still very much am, bisexual.

I tried to dial things back a little after seeing my son’s boner, but, to be honest, I found it very difficult. It was only a bit of sexy fun after all, and it wasn’t doing anyone any harm. Besides, the way he blushed and tried not to smile when he got a glimpse up my skirt or down my blouse was both adorable and irresistible.

What I did do, though, was casually start asking him about girls at school, and I was a bit relieved when he told me that there were a few that he liked. They were innocent crushes at first, and then I’ll never forget the day he told me breathlessly about his first kiss! I confess to having absolutely loved giving him the talk about boys and girls, and what they did, and what the results could be, and how to avoid them; I could see that it made him terribly excited. But I did also make it clear that it was all about love and affection and respect. The hug he gave me afterwards brought a lump to my throat and tears to my eyes. The hardon I felt nudging against my hip gave me a completely different emotion, and I eased myself away, just a little.

After that, he began bringing girls home after school to ‘do homework together’ in his room. I didn’t tell him to leave the door open, but he always did, which made me kinda proud. Not that it was all homework; I’d occasionally see red faces and mysteriously dishevelled clothing as they were suddenly a foot or so apart, their little chests heaving. It was adorable, but it wasn’t much later when I first gave him a string of condoms. “Mom!” he’d screeched, his face burning. But he still put them in his bedside drawer.

The first time that his door was closed was with a cute young girl called Melinda. Judging by the stifled giggles that I heard on the single occasion that I allowed myself to pass his room, they were having a lot of fun, and I wished them well while trying, and mostly failing, not to imagine what they might be up to.

She came around a few more times before it suddenly stopped. When I caught him moping around one day, I asked him about it. It turned out that her parents had found out what they’d been up to and grounded her; pretty much for life, he thought. I held him as he cried while remembering the first boy I’d loved and lost, and I ended up in tears as well.

With the resilience of youth, about a month or so later Cindy arrived. Looking at her when I first met her, she seemed incredibly innocent and shy, but the dwindling supply of rubbers in his drawer over the next few weeks told a whole different story, and I made sure they were kept topped up. I thought that maybe they might start going steady, but one day he announced over dinner that it was all over. She’d met someone else, apparently. He kept his tone very serious and his face implacable as he told me that she’d been a lot of fun, but they hadn’t been in love or anything, and he was OK with it. Then he broke down, and my heart bled for him as I held and comforted him again.

He was not long sixteen when he brought Tessa into the kitchen to introduce her to me. I was instantly taken aback by her stunning beauty: she was a tiny, elfin-like thing, managing to be slender yet still shapely, with lovely pert breasts and the cutest face and huge dark eyes framed by the bangs of her long black hair. My less-than-kind first thought was that my son was punching well above his weight with this one.

Our eyes met, and she dragged Toby’s head down to her level. “Why didn’t you tell me that your mom was so beautiful?” she hissed at him, and I winced as she dug what looked like a sharp little elbow into his ribs; looking back, I think I fell for her a little even then. I do know that my heart was beating faster, and there was an undeniable warmth spreading out from my belly.

“Toby shrugged and looked confused, but rallied bravely. “Mom, this is Tessa. Tessa, this is--”

“Suzanne,” I interrupted, standing up and holding my hand out. “It’s lovely to meet you, Tessa. Please call me Suzanne.” Our gazes were still locked as I took her tiny little hand in mine and we shook. It was only Toby’s none-too-subtle cough that broke us out of our reverie.

Without much encouragement, and to Toby’s obvious dismay, she sat down at the kitchen table with me, and we began to chat about this and that. She was clever and funny, and a little naughty, and that was the very first time that I’d felt a pang of jealousy over one of my son’s girlfriends. I got so involved in our conversation that I was actually surprised when Toby finally lost patience and butted in: I’d forgotten all about him.

Much as I wanted to, I didn’t dare find an excuse to go past his room. I sat in the lounge, not watching one of my soaps, while my mind was filled with images of what it would be like to lie between her slender legs, and feast on what was undoubtedly a deliciously fragrant young pussy.

A few weeks - and three dates - later, on a Friday, they came to me, their little faces full of excitement and hope, as they stood there with their arms around each other’s waists.

“Would it be OK if Tessa stayed the night?” Toby asked nervously.

I turned to Tessa. “Where do your folks think you’ll be?”

“I told them I was staying at a friend’s,” she replied, with a smile that made me weak at the knees.

“A friend’s?” I asked, with a raised eyebrow.

“They didn’t ask,” she explained while squeezing Toby a little tighter. “I think they were just happy that they’d have the house to themselves for the night.”

I didn’t have to do much soul-searching: they both clearly wanted this very much. “Of course you can stay, sweetheart,” I told her. “We’d love to have you.”

I’m sure that they were trying to be quiet, but the noises of their lovemaking travelled easily through the thin walls, and I have to confess that I listened intently with my fingers inside my panties, brushing my sex. It was purely by chance that I drained my tumbler of water, and found I could hear even better by placing that between my ear and the wall. At that stage, the only sounds were her muffled soft cries, and I convinced myself that my son was licking her pussy. My own fingers were a blur, dancing over my clit and, as far as I could tell from her ecstatic moans, we came almost simultaneously.

My father probably wouldn’t have been very proud of me as I searched through boxes of his old things the next day, until I finally found what I was looking for. I guess that I wasn’t either, as I held the end of his old stethoscope against the wall, and then Blu Tacked it in place. Or as I masturbated as I listened to the now clear sounds of their pleasure, seeing in my mind’s eye her delicate frame wracked in the throes of orgasm drove me absolutely wild. But I couldn’t help the images I had of my own son with his hard cock plunging into her no-doubt tight pussy.

As I lay there afterwards, with my heart pounding and my pussy still throbbing, I swore to myself that I would never do it again. She was his girlfriend, not mine! In the end, it was the need for a post-orgasm pee that forced me to move, dragging an oversized T-shirt over my naked body and heading to the bathroom. As I came back, I ran into Tessa, similarly attired and probably on a very similar mission.

“Hi Suzanne,” she said, smiling sweetly.

“Hi,” I replied, my eyes drifting down to her lovely bare slender legs. The bottom of the shirt was so close to exposing her pussy, that, in the dark triangle at the top of her thighs, I thought I might just be able to catch a glimpse of it. Eventually it occurred to me that I’d been staring for far too long, but when I looked up, she was gazing equally avidly at my lower half.

“I’d ... erm ... better...” she said uncertainly, waving an arm vaguely in the direction of the bathroom. The movement of her arm caused the shirt to rise, only a little, but just enough for me to clearly see the bottom of her perfectly bald vulva and her tiny rose-pink lips.

A whimper escaped my lips before I got a grip on myself. “Yes ... of course.” As we passed each other, I inhaled deeply through my nose, and the scent of her sex was almost the undoing of me. “Night,” I managed weakly as I reached my door, and then looked back.