It remains an unwritten rule that the older a person or animal is, the more impressive a body they will have when they double-dose as an Animalian. It also seems to make them more susceptible to Regressive Hypersexuality Syndrome (more commonly referred to as 'frat boy syndrome'). The main reason that it's considered a rule of thumb and not a certified fact is because Horizon Labs was reluctant on officially studying it. As much as several of these senior citizens deserve a second chance at life and youth, their living relatives would understandably have some issues about their beloved grandfather or grandmother looking and acting like a horny college co-ed.
For a proper study on this extreme reversion of age, Horizon Labs would need to look for elderly people who have families who would approve for this experimentation or no families left at all. The latter could because of losing their families long ago or have been abandoned at nursing homes for so long that no one remembered who brought them there, including the elder in question. Considering the difficult tact this would require, Horizon Labs has unsurprisingly not been able to make any headway with this and would have to gleam what information that could from the occasional geriatric who would submitted for the double-dosing procedure.
Such is the case for one old Japanese man believed to be over 90. He seemed to be of relatively good health considering his advanced age as he still had most of his hair, even if time had bleached it pure white. However, his mental health was another matter as Alzheimer's had eroded pretty much everything about his identity. A discreet search for abandoned elders like him allowed Horizon Labs to acquire him for testing. The nursing home he was held was glad to relinquish him as he deserved a better existence and they need to focus their attention on other patients who were less hopeless.
As the old man was having trouble focusing on the present, getting consent from him was a bit of a task, let alone finding out what animal he wanted to be. Eventually, Aiko ended up making the big decisions for him. This was technically a bit on the unethical side, but Aomidori, as he would come to be known, was not unhappy with the results. And he had his first chance to show off his new body at the Retreat to Beat the Heat.
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Not all of the conversions at the orgy started with some people getting injected with the Animalian virus. There were plenty of Animalians there who had their vaccines deactivated and were more than ready to help people convert. One noticeable figure among them was a large Komodo dragon who was wearing just a simple silk robe and a headband with horns attached to keep his long hair out of his face. But what stood out for this Komodo dragon wasn't just his size and muscular bulk, but the face that his scales were blue-green, at least on the dorsal side, and his hair was white. While he didn't resemble a true oriental dragon, lacking the mustache-like tendrils for one thing, he was a very impressive specimen. Several ladies certainly thought so when the orgy started and he undid his sash and opened his robe, revealing scaly slabs of jade muscles and a long, thick lizard cock.
Soon, Aomidori found himself surrounded by at least four women. "Would you like to give us a good time?" asked one of them.
"I would, though you might be a bit small for me," said Aomidori.
"There's an easy way to fix that," said the first woman before she started licking the tip of his cock. It didn't take a lot of effort to get a small flow of pre flowing. And with that, the woman started changing, her face beginning to extend out into a reptilian muzzle as scales started appearing across her body.
"Don't waste all of his seed," complained another woman, "How are we going to change if you suck it all up?"
"There's plenty to spare, ladies," said Aomidori.
The first woman removed her growing muzzle from his shaft and said, "But I can help spread the dragon power." She started playing with her breasts in her hands, which were growing larger and rounder. As scales started spreading across them, she tweaked her nipples until milk started flowing. "Ok, girls, the dragon milk's ready."
As two others started sucking from her breasts, the first woman turned her back to Aomidori, allowing him to see her growing tail lifting higher to give a clear view of her glistening slit. Recognizing the invitation for what it was, Aomidori grasped her hips, which were wider than before, before slowing inserting himself into her needy hole. The woman-turning-Komodo dragon moaned as a second dose began entering her system, causing her to begin bulking up. Aomidori plowed into her, hastening her transformation into a Komodo dragon that was slightly shorter and less muscular than him, but very decently muscled and curved for a woman. Before long, Aomidori blasted his first load into his female for that orgy. But two more females had finished with their first dose and were ready for him to give them their second.
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After the Retreat to Beat the Heat, Aomidori was offered the job to be the official mascot for the Dragon King's Palace. He couldn't really think of a reason to refuse as the job would come with plenty of payment and perks. It certainly helped that he had a fan club, mainly made of the ladies he helped covert.