Dot woke, not knowing what time it was; the concrete mega-block walls didn't have windows to see the outside, since those could be opened or smashed in order to break lockdown. "Time?" she whispered, trying not to wake her brother. Her glasstab illuminated to show 11 AM. She looked at Will's naked form next to her as he slept. She couldn't believe that she had fucked him earlier that morning, finally having that incredible orgasm that she had been denied for what seemed like forever, but had really just been since the previous night. And he had cum inside her at the worst possible time of the month! Her hand went to her tummy, imagining his powerful sperm swimming around inside her, looking for her inevitable egg. She moaned at the thought, partly in despair, but there was another part of her that she didn't want to acknowledge, one that had been growing for the past 16 or so hours.

She grabbed her glasstab and ordered the "morning after" pill from JJ/Novapfi's website. She wanted same-day shipping, but they only offered next-day. That would have to do, and she hoped that it would come in time. She couldn't have her brother's baby! Her pussy twitched a little at that thought, and she moved one hand down to stroke at her vaginal lips, which were very engorged again. Why was she so horny lately? she wondered. Sure, she was generally more libidinous when she was fertile, but this was crazy, with the additional weirdness of being unable to orgasm without a real cock inside her, and Will having a similar issue. Was this some new COVID variant symptom?

She finished the order and glanced down Will's slim body to the cock that had filled her fertile body up with his forbidden sperm just a few hours ago. It was hard again! She leisurely played with her pussy as she stared at it.

"Bling!" She turned to her glasstab, which had a message from her cam channel. *Funds Multiplier: Multiple requests: More raw sex with your boyfriend!* She logged into her account, looked at how much she had earned that morning, and gasped...it was enough for an entire new wardrobe! And her channel was filling up with even more people than earlier...it seemed that word had spread.

Her pussy was very wet, whether due to the remains of Will's earlier ejaculation, her own fertility, or both. She gave her auto-cam the thumbs-up to start her video stream and climbed astride her sleeping brother in the cowgirl position, holding a finger up to her lips as she faced the camera again. "Shh! My boyfriend's sleeping..." She figured that he wouldn't complain to waking up already being fucked; what man would? The fit blonde rubbed her juicy pussy lips along his hard shaft to lubricate it, and then slotted the head of her brother's cock in between them. She pressed down insistently, feeling his 7" hardness filling her needy vagina, and moaned.

"Cha-ching cha-ching!" her cam channel's funds counter sounded as she started to ride her sleeping brother's cock. She could feel her pleasure mounting, hinting at another massive orgasm to come...all it would take was another dangerous load of her brother's incestuous cum deep inside her...

"Muh?" Will stirred, confused. "Dot?"

"Ah, you're awake, Will--um, willing boyfriend! We're live!" She continued riding him.

He looked uncertain. "Um...no condom? Is that okay?"

She looked down at him, feeling powerful. "You already came inside me...what's one more load?" She winked at the camera.

"Chaching-chaching!"

"Really? Okay..." Will reached forward, grabbed his sister's rounded hips, and used them to pull her down harder upon his cock.

"Oh wooow..." Dot moaned as Will's full seven inches slammed into her again and again, the tip tapping at the entrance to her fertile womb. Soon, she knew, he would once again be blasting his hot cum right there, filling her up with another dangerous load, full of his incestuous seed. Her nipples got harder and she felt a small thrill move through the depths of her pussy.

---

"Chaching-chaching!"

Lindy woke up, drenched with sweat. She could hear some odd sounds coming from her sister Dot's room. As she sat up, the voluptuous brunette's large breasts swung forward and bounced back, and she hissed at how sensitive they were during this time of the month.

This time of the month...she moved one hand to caress her midsection. She had done her best to drip her older brother's dangerous sperm out of her after he had unknowingly inseminated her the previous night while he was sleeping, but she knew that there was still some deep inside, possibly within her fertile womb. She gasped as her nipples hardened at the thought of her brother's baby growing inside her.

After a moment, she got up, pulled on her tight t-shirt, and went to go see what that noise was. She didn't even think about putting on undies.

---

"Grab my boobs!" Dot commanded Will, and he reached up to fondle her B-cup breasts as she rode him. She moaned as his fingers found her nipples and lightly squeezed.

Unnoticed by the coupling teens, the auto-cam panned and zoomed back a little to capture 16-year-old Lindy standing in the open doorway to Dot's bedroom, her mouth open in shock as she silently watched her siblings fuck. Unaware that she was on camera, she moved one hand between her legs to play with her very wet pussy.

"Chchngchchngchchng!" went the funds counter. *Sister?* multiple people asked in the chat room.

Will was thrusting up into his older sister and she could feel that his cock was getting even bigger. "You gonna cum, big man?" she taunted him. "You gonna fill me with your dangerous sperm again?" Will's eyes widened. "Yeah, you naughty boy," Dot continued as she slammed her overheated pussy down on him, over and over, "I'm fertile right now, so we're taking a big chance here. You feelin' lucky?"

Oh God, Lindy thought as she desperately tried to cum from her fingers as she watched her siblings possibly try to make a baby.

"Oh God..." Will moaned, "Dot...I should pull out..."

"Don't you fucking dare!" she roared, and moved her face down beside his. She knew the auto-cam would pan away to not show his face, as she had directed it earlier, so she could whisper into his ear, "Don't worry, I ordered the 'morning after' pill. You can cum in me."

Will turned his face to hers and, finding it so close, kissed her. Dot was surprised, but so turned on that she let it happen. And then she was kissing him back, her tongue intertwining with his. With Will's face now obscured by her head, the camera panned to show the liplock.

*Aww* said someone in the chat room.

*Cum cum cum!* said someone else.

Will flipped Dot over into the missionary position and drove his hard cock into her fertile depths again and again. The telltale thrill of an orgasm started at the base of his cock and sashayed up, electrifying his nervous system as it pulled a massive load of sperm from his swollen testicles. Moments later, that load rushed up his shaft and erupted deep inside his older sister's unprotected pussy.

Dot felt his hot load inundate her primed reproductive system, which set off her own orgasm. "OHH! Ohmigaahhd! Willll!!" Her back arched in pleasure as she came, her needy pussy suckling on her brother's cock and drawing as much of his dangerous sperm as it could deeper inside her. "Uh! Uh! Uhh! Ohhh..."

"Me!"

Dot and Will, still gasping, looked over at the door to see their sister Lindy pulling her shirt off, revealing her large breasts and curvy brunette form. "Please! Me now!" She leapt onto Dot's bed and pushed Will onto his back, causing his spermy member to slip out from his older sister's pussy. "Yes!" Lindy cried out, climbing astride him and grabbing his still-hard cock.

"Lindy!" Will warned her, but she had already sunk her sopping pussy halfway down upon him. The funds counter was a continuous tintinnabulation now.

Dot, strangely unconcerned about her younger sister possibly impregnating herself on her brother's cock, grabbed her glasstab and looked at the funds total. She gasped...she could move out into her own apartment with this kind of money!

"Yes! Yes! Yes!" Lindy cried out as she rode her brother's cock. This was what she wanted -- no, needed: another orgasm like the one that her brother's cock had given her the previous night, the pleasure amplified by the dangerous thrill of fucking him unprotected. Besides, she thought, he had already cum inside her earlier...if she was going to get pregnant, another load of his sperm wasn't going to make a difference.

Will stopped trying to get his little sister off of him and was hypnotized by her large breasts bobbling up and down as she rode him. He pulled her down toward him and took one of her wide nipples into his mouth.

"Ohh!" Lindy moaned. "Oh, Will!"

Then he felt something tickling his balls. He let go of Lindy's breast and angled his head to see Dot behind her, his older sister's face between his thighs. She was licking his balls, he realized, and moaned. Then Lindy leaned down and pressed her lips to his. As they French kissed, with Dot stimulating his nuts with her tongue, he felt another orgasm rise up from there. Unconcerned about his little sister's monthly status, he pulled her hips down as he thrust up and blew another load into her vulnerable pussy.

"Mmhh!" Lindy cried out into his mouth as she felt her brother's hot sperm flood her ripe body, filling all the available space within her vagina and increasing the pressure on the entrance to her womb. Her own orgasm rushed through her, and as her cervix spasmed open, some of that flood of sperm slipped through, splashing upon the walls of her uterus. She reared up, arching her back in pleasure as her mouth lolled open, her higher thought processes shutting down as her body finally got what it had been demanding for hours. "Ah-huhh...!" she moaned.

Finally, she collapsed upon her brother, sated, and Dot waved her hand to stop the video feed.

"Why...? Lindy...?" Will whispered, barely conscious as his cock deflated within his little sister's well-spermed pussy.

"Shh, it's okay," she replied. "You rest now, my handsome big brother."

As Will fell asleep again, Dot remembered that she and Lindy's cycles matched, so she ordered another "morning after" pill before both sisters joined him in dreamland.

---

The siblings spent the rest of the day naked in Dot's room, always with her auto-cam capturing the action, filling her bank account as Will filled his sister's fertile bodies with the incredible amounts of sperm he seemed to be able to produce after only a few hours of napping. None of them noticed the chemicals that were being pumped in through the air ducts after each insemination.

The next day, when Dot's order arrived by drone, she was horrified to find two bottles of prenatal vitamins instead of the "morning after" pills! She called JJ/Novapfi, but after apologizing for the mixup, they informed her that their stocks had been depleted, and it would take days to replenish them. She hung up crying; it would be too late by then. She had no doubt from the sheer volume of seed that Will had injected into both fertile teens over the last day or so that they were going to end up knocked up with their own brother's babies. Abortion had been made illegal a long time ago, so they were stuck.

Drying her tears, she went back to her room to wake Will up for another round.

---

Experiment SNF-32A: Authorized Eyes Only

The new formulation induced the desired aphrodisiac effect. The genital engorgement was unexpected, but the discomfort made the subjects open to do anything to "relieve the pressure". Both effects, combined, worked very well to induce copulation, and the fact that they were siblings only delayed the desired end result by a few hours.

The modification to induce rest after copulation helped the male to replenish his supply of sperm quickly, as well as to provide time for his seed to soak into the females' reproductive systems.

As requested, fertile females were used for this experiment, and birth control was redirected. The resulting offspring will indicate if there are any genetic side effects from this formulation, as happened with SNF-1A, and because said offspring will come from the same gene pool, genetic drift that could interfere with the results will be minimal.

On a personal note, I'm including a link to "Darling Dot's" cam stream archive for those few days, as well as my personal login. Her production values are much higher than what our micro-cams in the vents are capable of.

Dr. <redacted>, R&D division 13, JJ/Novapfi.

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