It's about everyday land animals (deer, foxes, cats, dogs, wolves, birds, etc.) slowly gaining high intellegence and noticing what humans are doing to the planet, so they want to do something about it. Humans being humans, they start to kill the animals, hoping, with their newfound intelligence, they'll stop. But, the opposite happens. They get more persistent and a war starts. Once the animals learn how to use things like guns and cars, things turn out very differently. Almost the entire human race is wiped out. All but one small group of about 800 people. They've been hiding inside a base hidden inside the Kwajalein Atoll in the Pacific Ocean ever since the war ended eighty years ago. The main character is named Cyn (idk what kind of animal to make her, give me ideas in the comments. And yes, I named her after Cyn from Murder Drones lol) who lives with her mother in what used to be Vegas. She lost her father to a disease with no current cure. She ends up meeting a runaway young boy from the group on Kwajalein named Sadiki. They start off rocky, but end up coming to enjoy one another's company. Cyn tells her mother, Callista, about Sadiki, and she offers to help hide him, as she feels like they've met before.

I'll leave it there for now, but if you have any ideas on what kind of animal Cyn should be, let me know in the comments! I'm quite excited to give this idea a go!