The scientists were trying to create a substance that could change a person's sexual orientation to that of homosexual. It was an attempt at population control. In several places around the world, it was a fact that there were more births than deaths, and with the ever-advancing state of technology and healthcare, it was only a matter of time before there wasn't enough space on earth for humankind to reside on. So with population control in mind, a certain group of scientists had created a serum that, when exposed to a person (male or female), the person's sexual orientation would change, becoming totally homosexual. They would still be capable of having sex with someone from the opposite gender, but they wouldn't want to. If they no longer desired to have sex in a heterosexual manner, then they would no longer cause any children to be born ... and that was where the population control came in.
Unfortunately, there were some unintended side effects. With prototypes, there always were. In the case of the PC-1000 serum (PC standing for "population control", of course), it caused males who were exposed to it to become more "effeminate". They looked and behaved like twinks, all limp wrists and lisps. As for females, it caused them to butch up, both physically and mentally. The scientists were trying to correct this error, but unfortunately, it was right around the time when the accident happened.
The scientists were experimenting with the serum and it had somehow come in contact with a virus that had been genetically engineered by the same group of scientists (another project of theirs). And thus, the virus had bonded with the serum, causing what was basically a "gay virus". And it was very contagious, as people infected by it would transform simply by inhaling, ingesting, or coming into tactile contact with the virus.
They tried to contain the virus, but in less than a day, every scientist in the lab had been transformed by it, all the men becoming twinks and all the women becoming butch dykes, every one of them more interested in their gay orgy than stopping the virus from getting out.
And get out, the PC-1000 Virus did. After about a day or so, the virus made its way to the nearest town, and that's where this story began ...
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