Take a walk on the wild side.
There's a little girl with green hair who grows up in a forest raised by random animals, and then when she's older some hunters come and take her to civilization. A psychiatrist tries to "civilize" her, and she's upset and then she destroys his house and runs away back into the forest.
I think the book is trying to say that wild things belong in the wilderness and we shouldn't try to domesticate them. To the extent that at the end the psychiatrist's pet dog and cat are in the forest too, playing happily. The rabbits and bears and squirrels and the birds and the dog and cat and little girl are all playing happily together like some kind of Garden of Eden magical forest where no creature eats any other creature. Is this a universe where all the animals are intelligent? The bear is catching fish. Are the fish not intelligent? Are they just food? When the girl was raised in the forest, it says that birds taught her how to speak, and bears taught her to eat, and then she's playing with bunnies and stuff. She's in some kind of magical pastoral world, where all of the animals, predator and prey, get along just fine. And whenever you see the the dog and the housecat of this psychiatrist, they're just miserable-looking animals, until the girl comes along and they run away into the forest, without their collars and clothes.
Is the author trying to say, "Don't have pets"? It's not explicit, but maybe that's what they're going for, like PETA. Animals should not be forced to live in people's houses. This book is goofy. Did the author not realize that a cat that's been presumably an indoor cat all its life is not gonna survive in the forest? That bears eat squirrels and rabbits?
The last words are, "Because you cannot tame something so happily wild..." Why is it not a period? It seems like they're going to start another sentence, but that is absolutely the last page. It's got the endpapers on the other side of it, so it's not like a page is missing. Maybe it should be, "Because you cannot tame something so happily wild... unless you actually take his or her needs into consideration." Because clearly the psychiatrist and presumably his wife are just like not respecting her as a human being, and they're just getting like mad at the noises that she makes, and upset when she's making a mess. Just getting mad at children for being children doesn't work. It doesn't help somebody to simply get upset at them for being who they are, for not having learned how to do things your way.
The only humans that she encounters are ones who immediately take her out of where she was living, and ones who immediately try to force her to act like them. Of course she's not going to enjoy being among people if that's what's going to happen.
Maybe there's some kind of metaphor here about cultural assimilation? It's really hard to tell what this author was intending exactly. The only information we get about her in the back of the book is that it's her first book and that she was born in Hawaii. It is pretty, though.