The Amefurikozō (雨降り小僧 "Rain Child") is a spirit of Japanese folklore illustrated by Toriyama Sekien in his book Konjaku Gazu Zoku Hyakki.
Amefurikozō In the literature
In the explanation text, it is written that "speaking of the rain god Ushi, there is the amefurikozō, working on his jidō（雨のかみを雨師（ushi）といふ 雨ふり小僧といへるものは めしつかはるる侍童（jidō）にや )," saying that they are the jidō (children employed by the nobility) of the Chinese rain god Ushi.
Since Ushi (雨師) is an honorific title of the nobility (大人, "ushi"), and since jidō (侍童) can be understood as jidō (児童) meaning "child," it can be interpreted that this yōkai is a play on words to mean "a child employed by an adult."
In the kibyōshi book of the Edo period, just like the character tōfu-kozō, they appear as yōkai playing the role of servants.
In the kibyōshi "Gozonji no Bakemono (御存之化物)" by Jihinari Sakuragawa and illustrated by Utagawa Toyokuni in (1792), when a man walks on a rainy night, a one-eyed amefurikozō wearing a bamboo kasa and clutching something in both hands.
Because they appear on rainy nights, and because they possess something in both hands, they can be confused with the tōfu-kozō who also appears on rainy nights holding a tōfu.
Amefurikozō in Modern literature
For literature about yōkai published after the Shōwa period and during the current Heisei period, there are theories that if one stole his umbrella and wore it, one could never take it off again, or that he enjoys wetting people and seeing them upset.
According to the explanations of Mizuki Shigeru Road, in Sakaiminato, Tottori Prefecture, the amefurikozō would have the role of regulating rain, something that is strongly related to each person's life and work.
In the part titled "Amefurikozō" of Norio Yamada's essay "Tōhoku Kaidan no Tabi," there is a story in which, in the Kamihei district of Iwate Prefecture, a fox asked an amefurikozō if he could make rain fall, because there was to be a fox wedding, and when the amefurikozō moved the paper lantern the rain suddenly began to fall, and the fox wedding could take place.