Question

Why people call ninja is a Demon
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Answer 1

Answer:

It is difficult to pin down the emergence of the first ninja, more properly called shinobi—after all, people around the world have always used spies and assassins. Japanese folklore states that the ninja descended from a demon that was half man and half crow. However, it seems more likely that the ninja slowly evolved as an opposing force to their upper-class contemporaries, the samurai, in early feudal Japan.

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