One of the most appealing things about the Animalian virus is not only does it heal just about any disease or injury, but two doses of it can restore a person back to their prime and in better condition than they were before. However, the age-altering effect is also a double-edged sword. A double dose can also age any child or teenager into young adulthood. This aging exposure is obviously much more controlled. Only teens with permission from their parents or legal guardians could get a double dose. Still, accidents are bound to happen, such as what happened with the original Outbreak. And even afterwards, there are a few aging accidents, mostly involving unguarded milk.
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It all began with a cookie. Bill was told that the glass of milk he was given would make him a real cowboy, just like his dad was going to be. Of course, to 9-year-old Bill, milk had to be drunk with cookies. He had gone back the vending machine in the lobby to get some cookies. There weren't any chocolate chip cookies, but peanut butter cookies would do. After making his purchase, he hurried back to his changing room. But he paused when he got the various doors. Which room was his again? The doors looked all the same. After a bit of hesitation, Bill opened one door.
There was somebody already in that room, a girl not much younger than him. The girl looked up and smiled brightly, "Hi there."
"Oh, sorry, I was looking for my room," said Bill.
"It's ok. Are you going to be changing too?" asked the girl, "Oh, by the way, my name's Lulu."
"My name's Bill," said Bill, putting his glass of milk down on a table next to another glass of milk, "You haven't drunk your milk either?"
"I'm kinda nervous," said Lulu, "Sunny, I mean, Mommy is going to be a horse lady and she wants me to be a horse girl. I don't know if I wanna change."
"I know," said Bill, "My dad's going to be a big bull and he wants me to be a cowboy. I wanted to have some cookies before the big change."
"Ooh, can I have some?" asked Lulu.
"Well, ok," said Bill, "There's enough for both of us."
The two of them spent more time talking, learning what they had in common. For one thing, they both had single parents. Bill’s mom had been gone for some time and Lulu had been lucky enough to be adopted by Sunny, though she was still getting used to calling her ‘Mommy’.
Eventually, the peanut butter cookies ran out and it left them feeling rather thirsty afterwards. “Well, I think it’s time we drink our milk,” said Bill, picking up a glass, “Dad’s probably wondering about me now.”
“I think it’ll be fun to be a horse,” said Lulu, picking up the other glass. The two of them took big gulps from their milk.
“Oh, I just remembered,” said Bill, putting his milk down, “Dad says I should take off my shoes before I change.”
“Oh yeah, me too,” said Lulu as she started taking off her shoes. They were both feeling changes going through their bodies as they got their feet bare. They were just starting to change as their toenails grew darker and stared covering up the rest of their toes. Though they didn’t quite notice that Lulu’s toes were becoming cloven hooves while Bill’s toes became solid hooves.
However, they noticed when they looked at each other’s face. “What kind of cow are you becoming?” asked Lulu, seeing Bill’s face stretching out into a longer muzzle.
“I was gonna ask what kind of horse you were becoming,” said Bill. Lulu’s muzzle was much blunter and her ears stood out to the side more. In contrast, Bill’s ears were moving straight up his skull.
But it wasn’t until their tails grew that they realized what was wrong. Lulu’s tail was covered with short, chestnut hair except for the tip that had a distinct tuft. “That’s not a horse tail, that’s a cow tail,” said Bill, pointing.
“And you’ve got a pony tail,” said Lulu, pointing at the longer hair that was growing from Bill’s new tail. As their transformations completed, it became undeniable what their new species were. While Bill had become a colt, Lulu had become a calf.
“Oh no, oh no, we drank each other’s milk,” said Bill, feeling his longer equine muzzle.
Lulu held her new tail and said, “I’m not supposed to be a cow.”
“Oh man, Dad’s gonna freak when he sees this,” said Bill, getting more panicked, “What am I gonna do?”
Then Lulu noticed something that would change everything. “Hey, we didn’t drink all of our milk,” she said, pointing at the glasses that still had milk in them.
“So?” asked Bill.
“All we have to do is drink the milk we’re supposed to drink and we’ll be the right animals,” said Lulu.
“Is that how it works?” asked Bill.
“If it doesn’t, we’re already animals,” said Lulu, “What else could it do?”
Of course, many parents didn’t tell their kids the effect of an Animalian double-dose for the express reason of not wanting them to try and grow themselves up. Unfortunately, in situations such as these, that ignorance would backfire. Bill thought he could at least tell his dad that he tried to drink out of the right glass, even if it was too late. Bill and Lulu each took each other’s glass and drank the last of the milk in them.
At first, it seemed nothing would happen. Bill and Lulu didn’t feel like they were changing into the animals they were supposed to be. But then they started feeling a warmth spreading inside them. It didn’t seem like anything more than that until they noticed everything was starting to get shorter. “I think we’re starting to change,” said Bill.
Lulu felt her face and said, “I don’t really feel that different.” But her voice wasn’t as high-pitched as it was before. And then she noticed that Bill’s stomach was getting more exposed as his shirt pulled up. “Bill, I think you’re growing,” she said, pointing.
Bill quickly saw how Lulu’s clothes were shrinking on her. “So are you,” he said, his voice slightly deeper. Quite soon, he felt his clothes starting to pinch him. “We have to get out of these clothes before they’re too tight,” he said as he struggled to get them off.
“But what about-“ started Lulu before she felt her shorts digging into her waist. “Oh, alright,” she quickly agreed. The two of them struggled to get undressed before they were constricted in their own clothing. Of course, the clothes were far more likely to rip on their growing bodies, which made it easier to get them off. Any question about leaving their underwear on was becoming moot as the elastic was already tearing apart as they went into their tween years.
It was around this time that their hormones started activating. Lulu noticed that Bill was looking rather tall and handsome now. Bill was starting to see Lulu as cute, a different kind of cute than he ever thought about. “Lulu, can I ask something?” asked Bill.
“Sure,” said Lulu, getting excited from hearing his deepening voice.
Bill’s heart thumped a little harder as he asked, “Can I…kiss you?”
“I was hoping you would,” said Lulu, stepping up to him and noticing he was getting taller than her. They pressed their lips awkwardly at first but became bolder as new instincts began to take hold. Their bodies pressed together before they suddenly felt something between them. They both back up to see that Lulu’s chest had started pushing out into rounding orbs. Lulu cupped her growing breasts and said with a deeper voice, “It looks like I’m getting my udders.”
By this point, Bill’s underwear was only hanging on by the thinnest of threads, but a new pressure made them snap completely. Looking down, they could see his testicles had dropped lower and were growing bigger. His new sheath looked engorged before his penis slid out of it. Bill instinctively grabbed the shaft and moaned at the pleasure he received from it. “I’m starting to like being a horse,” he said, his voice sounding more mature.
Lulu’s underwear had already been destroyed by her widening hips and growing butt. As she looked at Bill’s penis, her own groin tingled as her vagina started getting wet. “Does it feel as good as it looks?” she asked, her voice getting a huskier tone.
Bill grinned back at her and said, “I think I can show you.”
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Meanwhile, Stanford was looking for his son. He had left off doing a little longer than he should have. His new bovine libido was a bit more powerful than he expected. He had to jack off twice to get his dick to go down, but it felt like it could spring back up at any moment. The doctor warned him there may be a chance that a double dose would cause RHS, he forgot what it stood for, but Stanford assumed it wasn't that common. Just because he's been alone since his wife died didn't make him a pent-up stud, or bull in this case.
But when Stanford finally got himself calmed down enough to check on Bill, he wasn't in the changing room he left him in. Stanford assumed he might be down in the lobby, but he wasn't there. He was starting to get a little worried. And he couldn't just keep walking around in just the dressing gown the doctors gave him.
He went back to the changing room and saw another Animalian. This one was a blonde mare who was also just wearing a dressing gown. Like other Animalian women, she had an incredible body with wide hips, a round ass, and huge breasts that had a lot of space between them exposed by the robe. Stanford's stronger bull nose could smell the sweat and musk on her. Obviously, she's spend a fair amount of time pleasuring herself after her transformation. This all made Stanford's dick start to get hard again, but he fought it down. "Uh, excuse me," said Stanford, "Have you seen a little boy? He's probably a calf by now."
Sunny turned to look at the big brown bull. He was definitely as tall and muscular as the advertisements depicted. He also had a very enticing musk and she could see his gown was bulging at the crotch. Sunny felt herself starting to get wet again, but she controlled herself. These new equine instincts were going to take some getting used to. "No, I was just about to check on my daughter, but I thought I heard something," said Sunny.
"Like what?" asked Stanford as he tried to listen. His new bovine ears didn't appear to be any sharper than when he was human, but what little wear they've had over the years had been healed. Still, as he got closer, it wasn't that hard to hear the sound of grunting and moaning. He felt his dick getting harder in response. "It's just a couple trying their new bodies," said Stanford, trying not to imagine too hard about what they were doing.
"Except this is the room that my daughter was using," said Sunny with concern. She had been denying the possibility, but saying it out loud made her feel certain. Before Stanford or her doubts could say anything, she opened the door and looked in.
There was definitely a couple trying their new bodies. A big brown stallion was on the bed, fucking a chestnut cow beneath him. At first, Sunny thought she had gotten the wrong room and she had just intruded on this horny couple. But she recognized the cow's chestnut curls and things start to click together. She was still processing this when the cow that was apparently Lulu let out a big moo and the stallion whinnied as they apparently hit their climax.
Stanford watched the primal scene with shock and growing arousal. His dick was fully hard and threatening to push his gown open. It was hard to say if he recognized the stallion as his son before he looked at the doorway, saw the two of them there, and asked, "Dad, is that you?" The stallion quickly pulled out of the cow, leaving a short liquid trail, and got off the bed.
"Bill?" asked Stanford, now recognizing his son's eyes in the stud before him.
"That's your dad?" asked the cow, looking at Stanford. Now that Bill wasn't covering her, Stanford could see she had an equally curvaceous body to the mare, her tits even bigger. The cow was giving him a rather lustful look.
"Lulu, what happened here?" asked Sunny. She pointed at Bill and asked, "Why is he here?" She tried not to look at Bill's chiseled chest or his long cock which was still hard.
"It's my fault," said Bill, "I went to get some cookies with my milk and I went to her room by mistake. We talked a while, ate the cookies, and we accidentally drank the wrong milk."
"Hey, it was my fault too," said Lulu, getting off the bed, "We hadn't drank all the milk so I suggested that if we drank the milk we were supposed to, we'd become the right animals. But we didn't really change...like we'd thought..."
"So you double-dosed," said Stanford, putting a hand to his forehead with a groan, "I should have warned you about that."
"I'm really sorry, Sunny, I mean, Mommy," said Lulu.
"Do I look like I can be your mommy now?" asked Sunny with a tone of resignation. Thanks to the double-dosing, they were both about the same physical age and Lulu looked ready to be a mother herself. When Lulu's ears drooped, Sunny let out a sigh and said, "I'm not mad at you, Lulu. It was a simple accident."
"An accident with lifelong consequences," said Stanford, "Now they're stuck like this."
"Well, we just have to make the best of it," said Sunny with a shrug.
"The best of it?" asked Stanford flatly.
"Of course," said Sunny as she walked over to Bill. "Like how Bill here became such a hot, fucking stud." She opened her dressing gown and let it slip off.
"Really? You're seducing my son right in front of me?" asked Stanford, though the sight of her bare backside with very arousing.
"Bill's a grown man now. He can make his own decisions. And feel free to have fun with Lulu if you think I'm bothered," said Sunny. She grasped Bill's cock and said in a sultry voice, "So how about it, Big Bill? You want to take this horse for a ride?"
Bill found that he couldn't say no to such a pretty mare, especially when she had him by the cock. "I think might enjoy that," said Bill before pulling her in for a kiss.
Stanford was so gobsmacked by this that he didn't noticed Lulu had approached him until she literally had touched his dick. Apparently his dick had finally pushed his robe open and he didn't notice until just now. Lulu was stroking his dick and looking up at him with her big cow eyes. "Can we have fun, Daddy?" she asked, "Sunny said it was ok and it felt so good."
"My name's Stanford," said the bull with a rigid tone, but he was losing the fight. Sunny had gotten Bill back onto the bed and was riding him now. He looked at the busty cow ready to please him and his lust finally overrode his reason. "But I'm going to make you scream 'Daddy' before long," he said with a growl before pulling her up and planting a big kiss on her. Lulu gave a squeak of surprise but soon melted into his arms. The kissing didn't last long as Stanford soon bent Lulu over and started plowing his cow from behind.
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After some extensive mating time, the four of them eventually calmed down and were able to explain what had happened to Horizon Labs. Bill and Lulu's double-dosing was ruled as purely accidental, though now they were considered legal adults and would have to attend WSA for the next four years. Both Stanford and Sunny were diagnosed as having milder cases of RHS, though it wasn't anything that couldn't be handled with a few treatments.
After that, it was simply a matter of the two couples moving into an apartment together. They obviously settled with their respective mates, but official marriage was off the table until Bill and Lulu graduated. Stanford found it hard to maintain the same father-son relationship with Bill. Right now, he felt more like an older brother. Sunny and Lulu's relationship was completely overhauled. Lulu hadn't been adopted long enough to fully form a mother-daughter bond with Sunny and with their ages so similar and their species so different, it seemed ridiculous to keep maintaining the mother/daughter roles. And yet they've never been closer. Sunny would admit she saw Lulu more as a best friend than anything familial, except as her husband-to-be's future mother-in-law, but the two of them have been getting along great and spending a lot of quality girl time together. It may not have been how Sunny intended to make a new start in Animalia, but now that she can bear Bill's foals and Lulu was in a good relationship of her own, she wasn't going to complain.