Why does Koume (or some other Kitsune) act like a teenager, when she is 60-something years old?

Kitsune society is very different from human society. Kitsune are foxes that turn into people, not the other way around. They immitate human society, but don't often live in it.

Kitsune families usually live in very large extended families. They also don't have to worry about the same problems that face most humans, since they are wild animals with super-natural powers. These factors promote a childish mentality and playfulness, even at relatively old age.

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I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.