Rachel

Rachel boldly walked down the hall towards her younger brother Jason's room as she heard Parker walk down the steps behind her. She couldn't wait to see her mother freshly fucked, but for now she had to satisfy her own desires.

She eased Jason's door open and slipped inside. Her younger brother was skinny and not very masculine, even at 18. He was sitting on his bed, scrolling through his phone with his back to her. She took her time to stand in a pose as alluring as possible before speaking up.

"What's up, Jace?" she asked, making her brother jump slightly.

"Hey Rachel, I thought you were going to be out late tonight?" he said, not looking up from his phone. Rachel smiled.

"I was going to, but Parker showed me something amazing, and I thought you should know about it too."

"Oh yeah, what's that?" Jason asked, finally turning. He almost swallowed his tongue when he saw his older sister, bare from the waist down and breasts much larger than they had been straining her thin tank top.

"Like the new me?" Rachel asked, pushing her chest out slightly, making her tits bounce. She could see Jason practically drooling as his shorts tented. "Well, some part of you does," she said, sashaying towards him, hips popping from side to side. He quickly tried to hid his erection.

"No, I mean, yes, I mean...sis, what are you doing?" he stammered, his face bright red. He stared at the bed, eyes flicking up to Rachel's body that exuded sex.

"I'm showing you the truth, Jason. Sex is so good, better than anything. I didn't realize it until Parker fucked me over the counter, but it felt so good. And just look at these tits." She hopped, sending her boob flesh quivering again. "I want to share it with you, Jason, the pleasure, the sex, the orgasm. I want to feel your hard cock inside me as you fill me with cum. I want to see your face as you spill yourself into my hot mouth." She was close now, leaning over Jason and forcing him to lie back on the bed. "I want to fuck you, Jason. And you should know your sister gets what she wants."

Without preamble, Rachel jerked her brother's shorts and boxers down, letting his stiff length bob free. She immediately dove at it, sucking it into her mouth and slurping at it, coating it with her saliva. She gobbled his cock, licking at its tip and shoving it into her throat until she gagged. It was big too, bigger than Parker had been, at least before he transformed. She blew her brother, enjoying his dick twitching in her mouth.

Jason suddenly began thrashing around, trying to push Rachel's mouth off of himself. She didn't give up though, only sucking harder. A second later, he yelled loudly, voice ringing through the house as he came, filling his sister's mouth with his seed. Rachel drank it eagerly, swallowing ever bit of it. Once he was done, she sucked one last time before pulling her mouth off of his still hard length with a 'pop'.

"Mmm, that was delicious, little brother. Now how about round two?" She positioned herself over his dick and sank down on it. What little hardness had left it quickly came back as Jason gasped at his sister's tight pussy. He was helpless to stop her as she began to ride him, bouncing up and down on his powerful length. Unable to stop, Jason gave in, fucking his sister back.

His slim hands trailed up from her gyrating hips to her undulating waist before stopping at her heaving breasts, still held tight in their cloth prison. Jason tore at the material, the fabric parting easily from how strained it was already. He groped his sister's large breasts as she shrugged the remains of her shirt off and removed his own.

"Oh, fuck, these are so good. I want these," he groaned in a daze, his mind already overrun with the virus.

"They're all yours, bro, any time you want them, as long as you give me a good helping of cum," Rachel said breathlessly, feeling her release approaching. She came hard, her love tunnel clenching rhythmically around her younger brother's penis as he squeezed her tits. She came down and immediately resumed her pace, her desire to feel her other brother cum inside her overwhelming.

"I don't want your tits," Jason grunted, barely holding his orgasm back as his sister experienced her own. "I want tits of my own. I want to be a woman," he said, his deepest desire coming forth. Rachel looked at his quizzically as she rode him.

"So my little brother wants to be my little sister? You want to be a girl, with your own pair of knockers and a pussy to match? What a secret you've been keeping," she said, surprised by his confession.

"M-more than anything, fuck you're tight," Jason said, loosing himself as he felt orgasm building again. "I want to be a sexy woman, wear girly things, and be beautiful!" he yelled, thrusting harder into his older sister.

"Well that's good, because you're already growing tits," Rachel said, looking at her brother's changing form.

"What?" he asked. He looked down and, sure enough, small breasts were forming under his nipples. He touched one experimentally and was surprised at the **** sensation that ran through him, the flesh suddenly growing sharply. He palmed the growing tissue, gasping as it overwhelmed him. That was all it took to send him over the edge again, finally giving Rachel what she wanted.

Rachel moaned as she felt her transforming brother's cock shoot into her. She watched in amazement as his body changed, his face and shoulders becoming slimmer and more refined, going from slightly masculine to decidedly feminine. Brown hair grew out, becoming long, flowing locks. Blossoming breasts surged forward, getting larger and larger until they barely eclipsed her own. Hips and ass swelled slightly, matching Rachel's own and her firm butt. Most importantly though, she felt Jason's dick not shrink, but grow longer, reaching deeper inside her. His cum flowed once again as his balls receded, tucking into his body, a new slit forming where they had once hung. Jason screamed again as his transformation finished, his voice shooting up octaves as the new futa's vocal chords reformed.

Finally spent, the two collapsed onto the bed, cock popping free of Rachel's full cunt. They gasped on the bed, Rachel looking at her new sister.

"Fuck Jason, you're sexy as hell. I'd certainly bang you if I had one of those," Rachel said, running her hands over her former brother's new boobs. The transformed sibling gasped at the stimulation, still not used to the additional erogenous zones.

"Thanks, sis, but don't call me Jason anymore. Now, I'm Jessie." The new woman leaned over and locked her older sister in a kiss, their tongues battling. Jessie even found the lingering taste of her own cum and made a note to get a full helping of her seed later.

"Oh, fuck, now Parker is going to want to fill you up too," Rachel said as they broke the kiss. "He's downstairs fucking a new sibling into Mom right now. Maybe once he's done, he'll do both of us too."

"Or maybe he can fuck me and you'll get another helping of futa cock. Wouldn't you like to be impregnated by your little sister?" Jessie teased. The two continued to make out until the younger of the two stood up, dick swinging between her legs.

"Come on, let's go find our brother and mother. I need to break in this new pussy."