Yamako

Jué yuán (玃猿) (in Chinese "Jué yuán", in Japanese "Kakuen") is a legendary animal in the legends of China. They are also called Jué (玃) (in Japanese "kaku"),Jué fù (玃父), Jiā (猳), Jiā guó (猳國) (in Japanese "kakoku" カ国 ), and mǎ huà (馬化) (in Japanese "baka"). They are similar to monkeys, and thus possess a characteristic of carrying away human females and violating them.

According to the medical herb book Bencao Gangmu (本草綱目), they are bigger than monkeys, and according to the Baopuzi (抱朴子), a míhóu (獼猴, meaning rhesus monkey) that lives for 800 years becomes a yuán (猨, ape), and if they live for 500 more years, then they become a jué, it can live 1000 more years.

In the Bencao Gangmu, it is written as 玃 ("jué") and 玃父 ("jué fù"). A "jué" is a monkey that has grown old, and has a dark blue color. It walks like a human, and they often kidnap humans or objects. There are only males and no females, and therefore they would abduct human females and give birth to children.

According to In Search of the Supernatural (Sou Shen Ji, 搜神記) and a book titled Bo Wu Zhi (博物志), under the names 玃猿 (Jué yuán), 猳國 (Jiā guó), and 馬化 (mǎ huà), there is as follows. They live in the mountains in southwest Shu, and resemble monkeys, and with a height of about 7 shaku (about 1.6 meters), they walk like humans. They live in villages in the middle of mountains, and when humans pass by, they distinguish between males and females by their scent and abduct women, and as their own wives, make them bring birth to children. The women who are unable to bring birth to children are not allowed to go down from the mountain, and after 10 years, their appearance and mind becomes the same as those kakuen, and lose their will to return to the human village. The women who give birth to children are allowed to return to the human villages along with their children, but since those who don't raise their children after coming back down to the village, the women would be fearful of that and thus raise the child. Like this, the child that was born from a kakuen and a human woman would have an appearance similar to that of a human, and when raised, they are no different from an ordinary person at all. Originally, the child's family name should be from the father, but since the family name of the kakuen, who is the father, is unknown, they take on Yang (楊) as a provisional family name. In southwest Shu where there are many people with the family name Yang, it is said that they are all descendents of kakuen. It has been pointed out that kakuen like these with these characteristics match with the cryptid called yeren.

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