Kumiho of Korea: Monsters of the World
The Kumiho (구미호) is a nine-tailed fox with shapeshifting abilities, who appears in Korean folklore, and originates from Chinese mythology. While it can change its appearance, usually into a human female, it still retains some fox-like qualities when it does. It is often depicted as evil, probably due to its tendency to feast on human heart and liver.
However, there is hope for the kumiho. If it can avoid eating human flesh for 100 (some literature says 1000) days, it can become human for good.
And how hard can it be not eating your favorite meal for 100-1000 days?
Map of the world courtesy of BYU Geography Department.