Vixens were once regarded as auspicious beasts, so why did they become a derogatory term?

In ancient Chinese literature, fox spirits were regarded as auspicious beasts and were regarded as spiritual creatures that brought good luck and happiness. However, with the development of history and the evolution of culture, the image of the fox spirit gradually changed into a negative image, which was described as cunning, flirtatious, evil, selfish and so on. One of the main reasons might be that in traditional culture, foxes were seen as a kind of monster that would harm human interests if it conflicted with humans. In ancient Chinese novels, fox spirits were often associated with supernatural forces such as ghosts and immortals, and their images were often associated with negative characteristics such as evil and cunning. In addition, the image of the fox spirit in some cultures was also given the meaning of eroticism and lewdness, which also provided the driving force for the evolution of its image. The image of the fox spirit gradually changed from an auspicious beast to a derogatory term, which also reflected the negative evaluation and misunderstanding of the supernatural power of the fox spirit in ancient culture.