Jason slammed his cock in and out of Keri's seeping, sizzling little fuck hole as his father rutted into her asshole. The two of them could feel the movements of each other's cock in Keri's belly, and found themselves tremendously excited by that.
"I can feel your cock in her guts, Pa!" Jason groaned.
"You bet, boy. Watch out or we'll tear her apart!"
They started timing their thrusts, slamming into her together, just as Joey pushed his cock down her throat.
Keri came and came and came, going insane with the continuous spasming of her wildly excited body.
Mark and Steve imitated them, rutting their cocks into Jody, fore and aft while the slender girl gargled in amazed ecstacy. Their big cocks pummeled her guts, whipping back and forth inside her and almost blowing off the top of her head with a tremendous cum.
***
Something about their brothers' and father's cocks kept Keri and Jody coming back for more, day after day. They were like junkies who needed their fix to get by. Both of them found it very easy to get addicted to the regular sex they now enjoyed.
They were both fucked a dozen times a day, at least. Both of them were to get used to multiple partners, and learn to love being fucked in the ass and cunt at once. In fact, they both did their best to turn the guys on, parading around the house in g-strings and the skimpiest of see-through nighties, the tiniest of bikinis and the tightest of jeans.
Neither of them ever slept alone now, sometimes sleeping in one of the boys' rooms, sometimes in their dad's, and sometimes with each other.
That was one of the things that turned out to be really popular. Their brothers and their father were always asking them to put on a show for them, and the girls were happy to oblige, stripping and going into a hot sixty-nine as the men watched in awe.
They even installed a hidden camera in Keri's room and had her bring Amy and Lauren over for a hot repeat of their sexual hijinks on the beach. Of course, Jody got involved too, and they watched the four girls fuck like mad, using their hands, mouths, and dildos.
Keri abandoned her wish to go to college. Who needed college with all these glorious cocks to service? How could she go away and leave them? She gloried in her body for the first time ever, revelling in its effect on her brothers and father, on the delights and pleasures the men brought to her.
How stupid she'd been, she often thought, to have waited so long before sampling her family's sexual delights. How stupid to have searched and worked and put up so much effort to date boys when she had such good cock waiting all around the house every day of her life. Now she was truly satisfied, and was sure she always would be.
Jody was happy as well. She stopped acting like a tomboy for the most part. She began dressing in girls' clothing like her father and brothers wanted. She attracted all sorts of attention, but ignored most of it in favor of her family's hot cocks and mouths. Had any family ever been happier than hers? she often wondered.