Odoro-odoro. A monster appearing in the Gazu Hyakki Yakō and various Edo Period yōkai picture scrolls. No description of it is known, but its name seems to be related to terms like odoro-odoroshii, an adjective describing something terrifying or eerie, as well as words like odoro-gami, a term denoting disheveled, bramble-like hair like that which covers the creature’s body. Otoroshii is also a Kansai dialect corruption of the common adjective osoroshii, or “frightening”.
Today, children’s yōkai books often describe the otoroshi as dwelling on top of the gates to temples and shrines, waiting for impious and evil-intentioned people to pass below so that it may pounce upon them. This behavior seems to stem from a fictional account in Yamada Norio’s 1974 book Tōhoku Kaidan no Tabi, and was likely inspired by Toriyama Sekien’s depiction of the beast perched atop a torii gate with a bird in its claw. (via)