I was using my twenty-one-year old stepson's new computer to do some graphic design and, when typing a website into his browser, URLs popped up for erotic stories. A quick scroll revealed that most of these stories were incest themed, and to do with sexual encounters between mothers and sons. A click or two of some of the jpgs in his history revealed a corresponding visual preference, for busty older women. This discovery did not shock me -- my wife and I are both very liberal and both have a background in sexual education. Freud may have been wrong about a lot of things, but the Oedipus complex is very real. Incest is one of the most popular genres of erotica, and "mom" is the single most searched term on videoporn sites. So, again, I was not so much surprised. Quite the contrary, I got an erection as I took in the reality of the situation. I was staring at proof that my stepson was masturbating and ejaculating imagining himself fucking a mother figure -- maybe his own mother.

As I said, my wife and I are sexually progressive, coming from what could be called a post-modern educational background. We are well aware that most young men fantasize about fucking their mothers. The difference between us and most people is that we don't intend to shame this impulse -- this just leads to repression and unhappiness. This isn't to say, of course, that we would advocate indulging the fantasy to the fullest degree, just that we know that to acknowledge it and even to use it as an opportunity for healthy sexual development is within the range of options.

I'll try to round out some of the relevant details before saying how the whole situation unravelled further than anyone expected it to.

My wife, Carrie, is 46 years old, about 5'6", tossed, raven black hair, large breasts, somewhere between average and curvy, with a lovely face and a sharp intelligence. In her everyday life, she's respected as the highly-capable, forward-thinking and queer-friendly professional that she is. In the bedroom, these same energies are funneled through her powerful sexuality. She's kinky; not so much whips and chains, but rape fantasies, anal play, and a lot of dirty talk. She is impossibly turned on by guys fucking -- especially an older, dominant male, and a younger, more submissive male.

Myself, Tony, am 48 years old , 5'11", brown hair, with an athletic build. I'm considered confident, masculine, and friendly in my professional life. I tend submissive in the bedroom. When I was 26, after a party, myself and a friend jerked each other off in front of my girlfriend at the time. I've never done anything with another man besides that, but the memory's lingered with me and still turns me on like crazy. Despite our openness, we've never invited another man into the bedroom.

Carrie's son and my stepson, Evan, is 5'9" with sandy brown hair and an average-slight build. He's a quiet, thoughtful student type, and has had one serious girlfriend until now. We know they had sex (even the time and place) since they came to us to discuss birth control, but they're broken up now. I happen to know that, unlike me, he's uncircumcised.

The three of us live in a small, modern townhouse -- Evan in the ground floor bedroom, us on the top floor -- and generally get on great.

So -- the evening after the day that I discovered evidence of Evan's porn habits, in bed after sex, I brought up my discovery. Carrie smirked but was not surprised. There is no doubt that my parental responsibilities were compromised somewhat by how turned on I still was by the whole situation. I suggest to her that I have a quick, non-confrontational sit down with him, just to let him know that it was normal, nothing to be ashamed of, and that we were okay with it. I thought it would be a great opportunity to disperse any of the shame that typically accompanies this practice that he might have built up.

The next day, after he got back from class, I had him sit down with me at the kitchen table. I was straightforward and told him that I had inadvertently discovered his incest fetish. At his panic and embarrassment, I was quick to tell him that I was not here to scold him, but that I wanted to assure him that this was completely normal and acceptable, and something that most young men did. As we were getting up, I even offered to send him some pictures of his mother that he might like. This surprised even me, but I rationalized it by telling myself I would send him G-rated stuff that would just demonstrate how accepting we were of his sexuality.

Later that night, on my laptop, I was picking and choosing photos to send. A couple bikini shots, one close shot of her face and cleavage, and, I decided, one borderline racy shot of her in just her nightgown, nipples just visible through the fabric. I attached all the photos but, before I hit send, I impulsively added one more from my stash of our erotic photos. It showed Carrie lying, angled back, on our bed, topless, her heavy mommy-breasts lying plump on her chest, with their raised aureolas, and pebbled nipples. Her crotch was in the foreground -- white cotton panties, with a few stray pubic hairs poking out the side. My blood rushed as I hit send.

I didn't receive any sort of acknowledgement that he'd received the message, but I knew he had, and my imagination started to go wild. Lying in bed, I couldn't sleep. I imagined my 'son' sitting at his computer chair, transfixed by his screen. First, he would flip through the relatively innocuous photos, and then arrive at his pretty mother, bare-breasted, vagina foregrounded but just concealed by a thin piece of fabric. He stare for a second, taking in every pixel of the image. He would immediately have a maximum-strength erection. He'd reach for it, grip it, feel its weight. He would firmly stroke his uncircumcised penis, foreskin whisking up and down, as in his mind he imagined himself penetrating his mother. His mouth on her mouth, his cock at her pussy. This would no doubt be the most incredibly erotic image he had ever seen, something that most young men dream of finding but never do. Eventually he'd spray his sperm all over himself, several spurts. And then, at last, the fantasy would break, and he would become aware of the cooling semen on his hands, his shorts around his ankles, and his mostly-nude mother laid out obscenely on the screen in front of him.

Almost like a mantra, a sexy thought refused to leave my mind. I was helping him come. I was helping him shoot. I was facilitating his pleasure and so in a way it was like I was right there squeezing his erection to a mind-numbing ejaculation, my hand sticky with his semen. I don't think I'd ever been more turned on in my life.

My arousal was engaged in an all-out war with my rational mind. And the pictures. Fuck. What would Carrie think?