In a world where no one has ever even considered eating animals a portly entrepreneur opens a shop selling animals, freshly killed, in animal-shaped coffins to customers with no concept of the will to purchase such nastiness. The venture fails to capture the public’s financial imagination. During a think-tank-thought-swim a rebel, a maverick, suggests, as a joke some say, that the dead animals could be heated up; their flesh made edible and sucked off the bone. This was tried and found to be nutritious and filling.
It was hard to persuade the public that actual beautiful cute animals could be eaten. But psychological training was used to help people cope with ingesting what seemed at first like inedible carcass.
Success grew bacterially.
Soon after, the meat diet became popular; everyone was happy. The downside was that eating human flesh became popular too.
Before the end of this horror story humans have eaten each other (themselves) into extinction. The last survivor, soon to be an a ex-survivor, eating himself out of sheer boredom.
The epoch of the non-human animals returns and the planet gets a nice long rest from humanity; until the next time, (this gives room for a sequel).