Tamamo-no-Mae is a kyūbi-no-kitsune ('nine tailed fox' - a fox that gains spiritual and ghostly powers is a kitsune, and they gain one extra tail for every century they train in their powers). She is often grouped in the Four Vilest Yōkai of Japan, the other three being Shuten Doji, Nurarihyon, and Sutoku Tenno.
Tamamo first appeared as a young and beautiful woman in the imperial courts of ancient Japan. Her beauty, grace, wisdom, exotic aura, and even her alluring scent instantly turned her into a figure of fame and power amongst the imperial members and government officials. However, she was eventually exposed and accused of being the cause of the emperor's sudden illness, resulting in Tamamo fleeing the court. She was eventually killed in a brutal war, and her body turned into the Sessho-seki (lit. Killing Stone), which was cursed by Tamamo herself so that all life within a certain radius from it would be cursed to death.
"Origin: China. A 9-tailed, golden-furred Tenko. She transformed into an unparalleled beauty to gain the heart of Zhou Wang. However, her countless atrocities led to the destruction of Yin. When this 9-tailed fox crossed to Japan, she became Tamamo. She found her way to Imperial Court, but Abe no Yasunari saw through her guise. She was shot and killed by Miuranosuke Yoshizumi and turned into the Sessho-seki."