The warning signs were crystal clear. We just chose to ignore them.
No-one had thought it was real, until it was.
Patient zero was Catherine Zegal. She arrived at the Birshof Clinic in Basel, complaining of extreme abdominal pain. An MRI soon revealed that her bones were being burnt from the inside out.
She was dead within three hours. Her skeleton continued to disintegrate for two more, before it was entirely consumed. The second recorded victim was the Ambulance driver who'd delivered her to the hospital. He'd collapsed in a cinema at the end of his shift, just nine hours later.
The Lago Laboratories in Zurich were the first to pinpoint the cause: a virus, encoded within the genes of our female common ancestor. Mitochondrial DNA that had laid dormant for thousands of generations, just waiting for the right set of point mutations to happen.
A set of mutations that burnt calcium as fuel.
But by then, the Hellfire was airborne, and unstoppable. By the time that the media had latched on to the story, over a fifth of the Swiss population had already been exposed to the virus. Flights were embargoed by the Swiss Government, but it was already far too late.
Slowly but surely, humanity combusted, leaving behind it just a thick film of oily residue.