Translated from Mizuki Shigeru’s Mujyara and Japanese Wikipedia
The takaonna (tall woman) is a yokai with an interesting hobby. If she is walking along, and sees a two-story brothel, she stretches the bottom half of her body so she can peek in on men enjoying the delights inside. It’s said that the takaonna was a homely woman who could never attract male companionship, changed into a yokai by her own desire.
Takaonna were first illustrated by Toriyama Seiken in his The Illustrated Night Parade of a Hundred Demons (Gazu Hyakki Yagyo ). He drew a picture and a name, but with no story or explanation for the stretching yokai.
Folklorist Fujisawa Morihiko first recorded the story of the ugly woman peeking into brothel windows in his book Complete Discussions of Yokai (Yokai Gadan Zenshu), although he speculates that the local legends of the takaonna probably came from people seeing Toriyama’s illustration, then imagining a story to go along with it. Novelist Yamada Norio furthered the legend of the takaonna in his book Travels in the Weird Tales of Tohoku (Tohoku Kaidan no Tabi). Yamada tells of a woman consumed by jealousy and lust but too ugly to get a man, who then transforms into the takaonna and menaces anyone enjoying the pleasures of the flesh that she was denied.
There is a possible (but obscure) connection to a more horrible creature from Wakayama prefecture, a female demon called the takanyobo (tall wife).
It is said that the takanyobo was once the wife of Kijishi, a woodcutter of Kizaku village. She was a strong woman who would go and cut wood with him in the forest. He thought he was a lucky man to have such a wife, but she was actually a yokai. Kijishi was a successful woodcutter, and he always kept a servant. But the servant wouldn’t stay long. Over a year, Kijishi went through 30 servants. It was only when his own baby also disappeared that Kijishi discovered the truth at last—his yokai wife had eaten them all.
Kijishi confronted his wife and threw her into a well. He thought to let her die down there, but to Kijishi’s surprise she stretched the bottom half of her body right to the top of the well, then clambered out and made her escape into the night.
The kanji for the tall woman is exactly what it says 高 (taka; tall) + 女(onna; woman). She is most likely an original creation of Toriyama Seiken, who apparently wasn’t feeling very creative because he didn’t give her a story. Fortunately the people of the Edo period filled in for him, and came up with a nice little urban legend based on his image.
I think the connections are obvious between the takaonna and the later kuchisake onna (split-mouth woman). Both yokai are urban legends more than folklore, both are hideously ugly women, and both have a grudge against the beautiful people they can never be, and the love (or sex) they can never share.
For more female yokai stories, you should read: