If you can't beat em, join em

Parker returned his attention to Rachel, no longer bothering with the counter girl.

"Sister... so hot... so hot.... SOOOO HOTTT...." he cried as he began letting out a floodgate of cum from his masturbation session.

This only made the counter girl more jealous. She needed that dick inside her... wanted that cum! And yet, he wouldn't share it with anyone but his sister? It wasn't fair.

Rachel looked at the girl sympathetically, seeing the jealousy plain on her face. "Sorry, hot stuff. I'll fuck you though, you're really sexy," she offered.

The girl started crying. "But I don't want to just fuck. I want him to breed me! I want to feel that mammoth meat inside me. Why should you get all the dick to yourself?"

Rachel shrugged. "I guess I'm just lucky. I'm happy to be Parker's fetish."

"God I wish I were you!" the girl complained as her envy grew. "I wish I looked like you. I wish I was blonde. I wish I were sexy. I wish my breasts were as big as yours. Maybe then he'd fuck me."

And as she shouted her wishes, her **** hopes activated the virus. Her hair began to lengthen, the color becoming lighter, and then blonde. Her naked breasts swelled as her ass widened.

Rachel, momentarily taken aback, then beamed. "Well it looks like you're getting your wish, sweetheart."

The girl opened her eyes in confusion, before looking down at her changing body. Her curves continued to inflate, as facial features rearranged themselves to be a match for Rachel's.

"Oh yes! YES! Make me like her! I want to be sexy like her!" she said to herself, as her altering pussy moistened.

But it didn't just give her curves and hair. It was all encompassing, altering every tiny detail to match Rachel's. The pitch of her voice changed. She aged a year to match Rachel's 21. Even her DNA became a perfect match, though there was no way either of them would know that.

And then, just like that, it was done. She was an exact replica of Rachel, in every measurable sense.

Rachel whistled. "Damn, I knew I was hot, but I had no idea I was this sexy. Plus, I've always had a fraternal twin, but now I get an identical one too," she said to her replica.

"Thanks, sis," the counter girl winked back. "I inherited it from you and our MILF mom."

Rachel laughed. "So you want to fuck? Not sure if that would be **** or masturbation."

"In a sec. There's still someone whose dick I want to feel first," she smiled. A moment later, the newly transformed blonde wrapped her arm around Rachel. She then called, "Hey brother. Like what you see?"

Parker had been ignoring all of this, having needed a brief (very brief) moment to recharge. However, his mouth fell open when he saw two of his sister, both looking at him with bedroom eyes.

"Come on brother. Don't leave your sisters waiting," they both giggled, their thoughts becoming progressively in sync.

Parker moaned. "Sisters... more sisters... two... so hot... SO HOOOOTTTT!"

Not waiting a second, Parker ran over and tackled the two sisters while they cheered him on. Soon, they entered a threeway that lasted hours. They did every position: vaginal, oral, anal, cunnilingus. Nothing was held back. And no matter how many times they orgasmed, it never took them more then a minute to get back into it.

By the sixteenth time they came together, none could remember which was the real Rachel. Both girls memories had faded away, replaced with an obsession with living in the now. Parker meanwhile barely had any thoughts left at all, aside from the obsession on fucking his sister. The fact that there were two of them made him the happiest man in the world.

And Parker's heaven didn't stop there. The rest of the night became a blur, as more people were added to the fun. An occasional shopper would wander into the gas station, only to become a new part of the sibling orgy.

The first was a young man, who took a wayward shot of sperm from Parker. He, like the counter girl, went through the same cycle. He ran, only to have the virus bring him back. Then, when Parker showed no interest in him, he would become another sister.

This happened repeatedly. The virus inside him and his sisters had mutated to accommodate Parker's fetish. Everyone they infected would become a new sister, a new Rachel.

Five sisters, ten sisters, thirty. All crying their brother's name as he spent each waking moment fucking as many as he could.