Wolf
One animal that is particularly good is the wolf. Wolves have a bad reputation, but actually they're very, very good animals.
When wolves are reintroduced to an ecosystem, good things happen. Overpopulation in deer and other animals decline, plants grow and create more habitats, and the balance of wildlife improves. It all starts with wolves, who are good dogs. Also, wolves take care of wild, abandoned kids. Only wolves do that, because they're good. Just ask Mowgli!
ろう
おおかみ
None
A wolf might be good, but if you run into one, all you can do is scream Oh 神!” (おおかみ).
"Oh 神," as in, "Oh god," because you're about to be eaten by a good wolf. You're part of the ecosystem now.