It looks pretty good except that I would change one thing....
Animals in this rp are slowly gaining the ability to turn into human. So it wouldn't be perfect, they wouldn't be able to hold their human image for long and some species of animals can do it while others can't (horses, bears, squirrels, etc...)
However creatures like wolves (big felines, dolphins, monkeys, etc...) are learning how to.
It has been noted in the actual Wolf's Rain there are radioactive areas (which could cause a mutation) but no one, especially animals, would go near it and these are hard to find because this is 200 years earlier than the story of Wolf's Rain, so there wouldn't be much radiation or wasteland.
The only type of human made mutation would be crossing wolf with human DNA and they're trying that out with Ethel's fetus growing inside her. It actually doesn't become successful until Darcia (in the current wolf's rain) is born, which is 200 years later.
But I would just change that. Maybe she develops the skill cause turning into a human is a mental thing for the wolves. She can be allowed to turn into a human, but it wouldn't be a mutation.
Other than that everything else looks good, even your other characters!