A Japanese mythological creature - more specifically, a youkai, traditionally depicted as an itachi (river otter) holding a kama (sickle) moving in a whirlwind.
There are three of them, who work in tandem; the first one knocks you over (with a club, according to certain sources), the second one cuts you, and the third one applies a salve to the wound; the speed with which this cycle happens accounts for their assocation with wind.
Kamaitachi are blamed for sudden cuts (frequently along the calf) recieved on blustery days with little blood, relative depth and quick healing. Some of the popular theories for debunking them involve plasma or little bits of sand.
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