Unfortunately for the girls, Dr. Vergunstien had crossed the boundary of reason. She was just far too horny to think straight. As she attempted to mull over the decision of which animal to impregnate the girls with, their moans and groans kept her focus on them. Their milk filling the canisters the machine was hooked up to higher and higher, their transparent skin showing their shared uterus getting assaulted by the dildo piston she had made.
It was just too much for her.
"UGHH!!" Dr. Vergunstien moaned, "I need to be a part of this!!" as she ran out the viewing area, dropping the tablet entirely. This caused her fingers to run over the tablet, activating all the testicles.
By the time the doctor had entered the main chamber, the uterus had clearly been booted up. Maria and Lilith could feel the testicles start producing large quantities of semen for their shared uterus to embrace. They could feel the rush of hormones shooting through their system, screaming at them to continue, overwhelming their brain with the need to reproduce.
Before they had a chance to view what was happening down there, Dr. Vergunstien jumped on top of the machine, mounting them.
"We're gonna be in for a long night, ladies," she said, before mashing her face into Maria's.
Maria barely had time to register the words before she could feel the doctor's tongue down her throat. It wasn't a human tongue, far too long for that, but right now Maria didn't care. She was too caught up in the heat of the moment to respond with anything but an attempt to return the favour.
Lilith wasn't left out. She was now receiving a breast massage, courtesy of Dr. Vergunstien's soft hands. The doctor was caressing her fondly, with the occasional squeeze spraying more milk into the suction cups it was attached to.
Dr. Vergunstien soon began switching up positions; sticking her tongue down Lilith's throat, shoving her pussy into each of their faces, even a bit of tongue in their ears. It caused the girls to get completely lost in the moments.
Soon, minutes turned into an hour, then two. As more and more time passed, the girls were getting bigger and bigger. Sperm and eggs continued to meet and develop inside of the pair. Humans were being grown in the same space as dogs, horses and kiwi birds, all of them vying for precious nutrients.
With more and more being produced by the second, space was soon forcibly made. Some fetuses cannibalised their neighbours like sharks. Others fused into each other, creating cross-breed hybrids that by all rights shouldn't exist, but with the nano-machines working overtime, they were too confused to know which was which.
It didn't matter. Soon, the machine began to strain. Despite the piston being at full power, the girls' uterus was so full, the piston began slowing down, then stopped entirely. The canisters of milk the machine was sapping from the girls began overflowing back into the tubes, then into the suction cups. Before long, nuts and bolts began flying off their positions and then...
CRACK!! FLICK!! WHOOSH!!
The piston flew off the machine and the suction cups were flung from their position. And the gates opened.
A rush of babies practically flowed out of the pair whilst the room was showered with milk. Humans and animals, the developed and half-developed, those pure or mixed alike, they all shot out of the pair onto the milk-covered floor. The girls also experienced the most mind-shattering orgasm they ever experienced. The sweet relief they had felt from the release of pressure was unlike anything they had ever encountered.
Suddenly, the room was swarming with staff, all of them "Dr. Vergunstien"s. As one ran to turn the pair off and another pulled the green and magenta doctor off them, other began bundling up the babes and carrying them out of the room.
As the paired came down from their orgasmic high, a tall buxom Dr. Vergunstien half covered in red fur and sporting two cocks came to check on the pair.
"Are you two alright?" she said. "I swear, that split one should never have accepted this assignment herself. She knows she has self-control issues."
As Lilith and Maria looked into each other's eyes, they used their new bond to read what the other was thinking before answering in unison.