A famous red orge (with the ability to change his look ) who lead a horde of Oni (demon) and terrorized Kyoto. He and his subordinates dwelled in a metal fortess which the built on Oeyama (Mt Oe) of Rokusai, Kyoto.
Shuten Dōji is said to be one of the greatest yōkai (demon) of Japan. His name ranked with that of the golden-hair nine-tailed kitsune (fox demon) of Tamamo-no-Mae (玉藻前) and Emperor Sutoku (崇徳天皇) who transformed into an Ootengu (greater tengu).
Together with Ibaraki-dōji ( 茨木童子), aka the oni of the Rashomon gate (羅生門の鬼), they led their horde of demon to rampage the capital city - robbing and kidnapping girl. In some legend, it was said that he can change his form to a beautiful youth to seduce virgins and slash off their breast to feed on -_-.
There various version toward his background. According to Otogizoshi (御伽草子), Shuten Dōji was a young monk who was had attrach various evil thoughts due to his look. Another saying was that, he was the son of Emma-o and a noble princess. Whereas, some legends say that Shuten Doji was originally a human robber, but became an oni because he killed too many people.
When the daughter of the nobleman Ikeda Chūnagon (池田中納言) was kidnapped, the great Onmyoji, Abe no Semei (安倍晴明) devined that she was captured by the Oni of Oe-yama.
Thus the emperor order the great swordman, Minamoto-no-Yorimitsu (源赖光), to slay the demon. He and his four men called Shitennou, namely - Watanabe no Tsuna (渡辺綱), Sakata no Kintoki (坂田金时) aka Kintaro (金太郎), Urabe no Suetake (卜部季武) and Usui Sadamitsu (碓井貞光), disguised themselves as yamabuse (Buddhist monks discipiling in mountains), then headed for the Mt. Oe .
On their way, Yorimitsu met three mysterious old men. The old men gave him a magic helmet and a bottle of magical beverage, Shinbenkidokushu . In fact, the three old men were the local gods of Sumiyoshi , Iwashimizu and Kumano .
They pretended fallen yamabuse and visited the castle of Shuten Doji in Mt. Oe . They were invited to the banquette and served human flesh. They ate the whole dishes so that Shuten Doji would believe their false identity. Doji believed, and drank from their bottle, the Shinbenkidokushu .
This magical beverage made Doji asleep.Then the final battle began. Yorimitsu and the four fighter assaulted Doji , sticking the spears through its body and cutting at it head. Of course Doji resisted violently.
When Yorimitsu cut away Doji's head, the disembodied head jumped to Yorimitsu and bit his head with its enormous jaws. Normal helmets would be easily destroyed. However, the magical armor managed to protect him.
The date was said to be January 25th, 990 AD.
The sword that was used to cut off the demon's head is since being know as the famous Demon Cutter Yasutsuna (童子切安綱 - どうじぎりやすつな),