Yokai are a Japanese pantheom of supernatural folklore spirits that range from demonic to the beneficial. They include monsters, ghosts, and demons, which aren't always separate categories as they are in the West. Kitsune is the one you are most likely to run into today.
Foxes are known for being cute and intelligent, so clever that it was easy to ascribe superpowers to them, which is exactly what happened in ancient Japan. The supernatural fox called Kitsune could be a mischievous prankster, a shapeshifter, a protector, a blessing, or a spirit that possessed humans, depending on the time and place. They are rarely 100% malevolent, but they can ruin your life in order to teach you a lesson. Kitsune can take a form of a beautiful woman, and in some cases even reproduce with humans to provide hybrid offspring or some form of Kitsune ancestry.
Dr. Emily Zarka explain Kitsune, from ancient tales (with many tails) to modern depictions in pop culture, including a bizarre (and clueless) American plan for weaponing Kitsune against the Japanese during World War II.
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