In Japanese folklore the female demon (oni) Hannya figures prominently. Often depicted in traditional Noh and Bunraku plays using a wooden mask of a fierce and grimacing horned demon, this malicious entity may be Japan's most well-known demon.
You may even recognize this mask as being the symbol of darkest moral depravity in Onibaba.
An ancient legend recalls how the female Hannya persecuted all who attempted to pass through the Rashomon gate of Kyoto. A staunch samurai named Watanabe no Tsuna decided to lay in wait for the demon in order to slay it, until he was eventually persuaded by a beautiful young woman to escort her into town. As they travelled, Watanabe happened to glance over his shoulder and saw the young woman transforming into a terrifying demon. As the demon then laid hold of Watanabe, he quickly wielded his sword and cut off the monster's arm. As Hannya fled screaming, Watanabe carefully wrapped the severed arm and later hid it in a secured chest.
After much time had passed and the event had faded into memory, Hannya disguised herself as Watanabe's aunt and thereby convinced him to display his "trophy" of Hannya's limb. Upon seeing her arm, the demon immediately reverted into her hideous appearance and, grabbing the arm, fled from the house of Watanabe.
The legend was captured in a ink painting by Zeshin Shibata (1807 - 1891) entitled Hannya Retrieving Her Arm.
Hannya Retrieving Her Arm (Zeshin Shibata : 1807 - 1891)
?? (Hannya) by Mizuki Shigeru