In the twelfth century, a woman appeared at the imperial court in Kyoto so learned and so beautiful that no one could account for her. She knew Buddhist scripture, Confucian classics, and Japanese poetry better than the scholars sent to test her. She was given the name Tamamo-no-Mae, and within a few years she had become the favorite of Emperor Toba himself — and, according to the story that has circulated ever since, the reason he nearly died.
What does she look like?
As a courtier, Tamamo-no-Mae is described the way any celebrated Heian-era beauty would be: pale skin, long black hair, faultless manners, an unnervingly complete education. There is nothing monstrous about her on the surface, and that is the entire point of the story — the danger is that she looks like exactly what she claims to be.
Underneath, she is a kyubi no kitsune, a nine-tailed fox spirit centuries old. When the disguise finally fails, artists show her true form breaking through: a white or golden fox with nine bushy tails fanned out behind her, sometimes still wearing the trailing court robes, caught mid-transformation between woman and animal.
The emperor's illness
Not long after Tamamo-no-Mae rose to prominence, Emperor Toba fell gravely ill with no physician able to explain why. The court eventually summoned the onmyoji (yin-yang diviner) Abe no Yasuchika, who determined through divination that the emperor's consort was draining his life force — that she was no woman at all. Confronted, Tamamo-no-Mae fled the capital, taking her fox form and running north to the moor of Nasu no Harano in what is now Tochigi Prefecture.
The court dispatched two warriors, Kazusa-no-suke and Miura-no-suke, to hunt her down. After a failed first attempt, the two men trained their archers in fox hunting on the moor itself before finally cornering and killing her.
The Killing Stone
Death did not end her. Tamamo-no-Mae's rage and venom, the story goes, passed into a boulder on the spot where she died. This became the Sessho-seki, the "Killing Stone" — a rock that gave off poisonous fumes and killed any bird, insect, or traveler that came too close, for centuries.
The stone's curse was finally broken by a wandering Buddhist priest, Genno Shinsho, who struck it with his staff and performed rites to release the spirit trapped inside. In the telling dramatized in the Noh play Sesshoseki, traditionally attributed to the Muromachi-period playwright Konparu Zenpo, the freed spirit confesses that Tamamo-no-Mae was only her latest disguise — that the same fox had, in earlier ages, ruined the Chinese court as the consort Daji under the Shang dynasty and worked comparable mischief in India before ever reaching Japan. A separate medieval prose tale, Tamamo no Soshi, tells the Nasu story on its own, without the continental backstory.
Where it comes from
Tamamo-no-Mae belongs to a much older East Asian tradition of the seductive fox spirit who topples rulers from the inside — a way of explaining a kingdom's collapse without blaming the king outright. Casting the blame on a bewitching outsider let storytellers criticize misrule while keeping the sovereign himself blameless, merely deceived. Emperor Toba's real reign was in fact troubled by succession disputes and factional strife that historians link to the later Hogen Rebellion, and the fox-consort legend reads, in part, as folklore's explanation for a court that seemed to be poisoning itself.
The Sessho-seki itself is a real volcanic rock formation near Nasu, and its natural hydrogen sulfide fumes — genuinely capable of killing small animals that linger too long — almost certainly gave the legend its physical anchor.
Tamamo-no-Mae today
The Sessho-seki is still a tourist stop in Nasu, ringed with small Buddhist figures called jizo. In March 2022, the boulder split cleanly in two, reportedly along an old repair crack widened by rain and freeze-thaw cycles, and the event made international news as "the stone that seals an evil fox spirit has cracked open." Shrine officials publicly insisted the seal still held.
Her story is also one of the few yokai legends that plays out fully formed in the Noh repertoire, still staged today, and the nine-tailed fox has become a recurring figure in modern Japanese games, including as a playable spirit in Nioh 2 and a servant class in Fate/Grand Order — both drawing directly on the Nasu legend rather than inventing a new character. The ukiyo-e artists Utagawa Kuniyoshi and Utagawa Kunisada each produced prints of her transformation in the nineteenth century, and those images remain the visual template every later version copies.