A teenager named Evan walked into a convenience store, looking for something to drink. He had just finished going for a walk while listening to some music, and took his headphones off when he walked inside the store. He walked towards the counter, The cashier was wearing an orange hoodie over a white shirt, and was turned to the side to throw away some trash.
“Can I buy a drink from here?” Evan asked.
The cashier heard Evan’s voice, and turned towards him—revealing his second head. The body’s left-hand side was half of an orange hoodie and full beard head, while the other half had half of a green hoodie, a shorter beard, a red cap, and a different face. The white shirt they shared also had two neck holes. Needless to say, Evan was surprised upon seeing this.
Both halves of the cashier—or cashiers—offered Evan two flavors of a new brand of soda called Polycephola. They explained that they drank it the other day—when they were still two separate men.
The reason Polycephola was a new soda was because it was connected to the lab accident that allowed the virus to escape from the underground lab in the first place. All of the scientists and employees there were aware of the viruses and the strange abilites that they possessed, many if not all of which involved things like multiplying its host’s body parts, fusing separate hosts together, and so on.
At least one of the viruses made its way out of the lab through an employee who was so ambitious and curious enough to try his own experiments at home. He had smuggled away a sample of said virus as well as an antidote, and took them home to his one-bedroom apartment. He began by putting a sample of the virus he took into the bowls of his two dogs—a black Labrador and a Golden Retriever. After tasting the water, the man whistled for his two dogs to come to him, and they did so. When they brushed against each other, they fused together—half of the new “Orthrus” was the Labrador, and the other half was the Retriever.
The man was amazed at what had happened, and then decided to try it on himself and a male friend. They mixed together their homemade soda, popped a sample of the virus inside, and each poured a glass. After drinking it and touching their sides together, they fused into a two-headed man, but obviously with different heads. They then tried the antidote, and successfully separated back into two separate men. They decided to leave the conjoined dog(s) as one body, since it was kind of cool to own an “Orthrus”.
They began branding their special soda and selling it around town, giving some to a few convenience stores as well as soda carts here and there—the antidote being sold separately. It soon became clear that only those who had the virus in their systems could fuse together, but the infected could not fuse with those who were not infected, and vice versa.