Editor's note: this story contains scenes of non-consensual or reluctant sex.
*****
After the bombshell that Mom had dropped when she told us she had a sister, Rosemary, and that she was at the event, Chrissy and I went back to our room for a shower. Our cunts and assholes were aching, but aching in an enjoyable way, that just reminded us of the fun we'd had being fucked by seventy-five or seventy-six men in the family, some more than once. When we went into the shower, Charlie was already under it. We joined him, but he didn't stay.
"Can't stop, girls. See you at dinner," he said.
"I bet he's going back to fuck one of the younger women he ate out, Susan."
"Bound to be, Chris. After all, he would have been able to work out which had the tightest hole when he was eating them, wouldn't he? But what on earth is going on with Mom and this sister she says she has? Even if we didn't know about her, how come she's here in the family given that it took me and Tony to get Mom to join in?"
Well, Chrissy didn't have any better idea than me. Given how shattered we were, we decided to have a bit of a lay down before we met Mom and the woman she said was her sister. To start with, we just chatted about our experiences in the afternoon, and which men we recognised who fucked us, to take our minds off the problem of our new aunt, and of course, we went to sleep.
The next thing we knew was Mom charging in to the room with one of the staff, who must have used a master key to get in, with an older woman behind her. Mom was in her robe, had her hands on her hips, and looked angry. Next to her was the guy who'd brought the breakfast the last two mornings, and I realised this wasn't just the third time he'd seen me naked, but I'd had been laid with my legs open, so now he'd had a really good look at all the interesting folds of my cunt as well.
"Fucking hell, girls, you were supposed to meet us in the bar an hour ago. Well, you're going to have to wait to hear Rosemary's story, because if we don't get down to the ballroom straight away, we're going to miss the lecture that's supposed to explain why our family is so into incest."
Shit, she was right, and I really did want to hear this, because I knew Tony had been working with the Professor who was going to speak, and he'd said that at last they were starting to understand how the incest trait really worked. Chrissy and I got out of bed, grabbed our robes, and followed Mom and the other woman down to the ballroom, as fast as our aching crotches would allow. When we got there, we saw it was set up for a buffet, presumably in the expectation that some people's attention spans would be exceeded if it were simply a set-piece lecture, and they could break it up by having a graze.
Once we'd got our food, we took it back to the table where the others were already waiting. Then a tall, handsome-looking man, wearing the same robe as the rest of us, of course, took to the stage.
"Good evening, family. I'm Professor Alex Banks, obviously from the Banks side of the family, and I'm a professor of Genetics in one of the famous Boston teaching hospitals. Firstly, thank you to everyone who provided a DNA sample for my studies, because it has really helped me start to get new insight into our family inheritance of incest.
"Now, I'm sure you're all aware that over the last half century or so, the standard explanation for how inheritance works is that it is all through DNA, which is essentially the blueprint that specifies how our bodies develop, our susceptibility to disease, and to a large extent how we behave. We all have two complete copies DNA, one of which we got from our mother, and the other from our father. When we reproduce, a single DNA copy is created in each egg and sperm, taking pieces at random from both our two copies.
"This explains an awful lot about inheritance, but not everything, and certainly not how our susceptibility to incest is inherited across all of the family, males and females. We knew there had to be something else, and more recently people have discovered what is called 'epigenetics', which is the area of my own research.
"Perhaps the best way I can explain what it is, is this. Imagine you have a long and complicated favourite recipe. Over time, you'll probably discover that you can skip one or two steps to save time, but yet that another step is really important. Maybe you prefer it if you double up on the amount of one ingredient, so you scribble all this in the margin of the recipe so you it all next time around. Now, the recipe is kind of like the DNA, and your notes are like epigenetics, not altering the basic blueprint, just how you execute it.
"Maybe this doesn't sound very dramatic, but it is. I'll give you a couple of examples. Firstly, in a colony of honey bees, the workers all have the DNA of a female, and therefore essentially are females. However, there is only one queen that lays eggs, acting like a female. There's still a lot that isn't understood, but what we know is that in workers the areas of DNA that code for reproduction are all turned off, a bit like scratching out something on your recipe. Those same areas, however, are turned on in the queen, and it is tied up with the fact that the queen is fed a different diet, including a lot more Royal Jelly.
"The second example is closer to home. We all have within us two collections of DNA which primarily determine our own reproductive performance, and a lot of shape of our bodies. These are called the X and Y chromosomes. Women have two X chromosomes, but one of them is essentially turned off. Men have one X and one Y, so have all the DNA needed to make them a woman, which would be a bit embarrassing unless much of it was inactive.
