Note: This story was dynamically reformatted for online reading convenience.
 
 "No, dear, spread them and pull back the hood--that's it, now your clit is
showing properly and I have a good view of him inside you," my mother said
and held the camera close to our joined sexes.  In the reverse cowgirl
position, the penetration wasn't deep but his cock hit my g-spot and it
looked beautiful, even if he was just a child and lacked the attraction of
a man.

   In truth, he was not only my lover but my son, as well.  Our family
tradition was to let the grandparents raise the young in order for parents
and children form a sexual bond when reunited after twelve years.  Thus my
relation to both my mother and son was sexual, but theirs was that of a
parent and child, and they had only joined me in bed for a threesome after
some hardcore seduction on my part.

   "Now you ride him," I said to my mother, after only a minute of
intercourse.  My desire was to bond them sexually as well, like my mother
once had bonded me to my granddad, the man who raised me.  I really didn't
like my granddad that way but mom didn't want to take my virginity with her
fingers.  She had been firm, and now I understood the thrill.

   My mother and my son shared a long, awkward look, and then I took
matters into my own hands and started undressing my mother.  She didn't
stop me and the boy had not said much since we started.  It had not been as
much seduction as coercion that had gotten him in bed.  He was still so
young, and I felt for him, but it was family tradition, and I had really
looked forwards to our reunion.

   "Maybe we should wait a few more years--" mom began but I cut her off
with a deep kiss and a hand down her panties.

   "I already took his virginity," I giggled when we broke lose, "it'd be
cruel not to let him cum now."

   The boy didn't say anything as I made his parental figure straddle him
the same way I had.  I took his dick in my hand and peeled back the tight
foreskin before placing the tip against mom's vagina.  She wouldn't take
him inside and I had to push her hips down.  For a moment I thought she'd
refuse but then the dick parted her inner lips and slid inside her pussy,
and she put her weight across him.

   "No, I'm sorry, I can't do this," she said suddenly and tried to get up
but I held her down.

   "Please, mom," I begged.  "It's already done, you have him in you, and
it has to feel nice, doesn't it?"

   "I'm not comfortable with this at all," she said but remained seated,
with the dick in her pussy.

   I chose to not answer, fearing whatever I said would make her leave, and
instead bent down to admire their sexes.  He was hard and she was wet, but
I knew it was unwanted for both of them.  Still, their bodies joined and I
knew I could make them fuck.  I gave them a long lick, starting at his
balls and continuing up over her clit.  Unlike my clit, hers stood out
between her lips and I sucked it hard, making her legs shiver.  She had
strong reflexes and as I pleasured her with my tongue, her hips started to
move until she was rocking back and forth, fucking her grandchild.

   "Now keep doing that," I told her sternly and got the camera to record
their forced love-making.  "Oh, look, I think he's about to cum."

   Mom forced her hips still, looking shocked.

   "Don't be cruel mom, you have to finish it now."

   She closed her eyes and started rocking again.  "Look at that," I told
her, turning the camera display so she could see, "he's ejaculating in
you."

   Mom stopped again and looked at the screen, panting softly.  A gob of
white ran down the shaft of his cock, proving he was sexually mature,
despite the lack of hair on his balls.  I scooped it up with a finger and
pressed it to mom's lips.  Her tongue darted out, seemingly before she
could think, and then she looked as if she had been kicked in the guts.

   "Granny?" the boy asked, startled.

   "She's having an orgasm, like the one you just had," I explained, "go
ahead and hump her."

   "No," mom panted and the boy hesitated.

   "Do it," I told him sharply, "fuck your granny senseless."

   The boy obeyed, and mom slumped forwards, supporting herself on hands. I
smiled at her, triumphantly, and then did something I had not planned to
do. I straddled his head and pushed my pussy in his face.  He had plenty to
make up for all the pain he caused me and I needed to cum so badly.  I had
to ride his face, he didn't know he was supposed to lick, but it was just
as good and I came hard when mom had recovered enough to turn around and
watch what I was doing.  Her eyes went from my face to between my legs.  I
held my lips apart, the way she liked my pussy, exposing my horny little
clit.

   Then it was my turn to cum and I buckled while looking mom in the eyes.
I struggled to keep my eyes open as pleasure tore at my senses, loving the
excitement in her eyes, as I came for her on my sons face.