Night has fallen. You’ve had a hard day at work, and you’re walking home, cutting across a grassy field to save time. All of a sudden, a huge gust of wind knocks you to the ground. When you stand, you happen to look down and notice that your pants have been sliced open at the calf, and a closer look shows an inch long slit in your skin. There is no blood, and no pain. Yet, anyway. The pain will set in later, and you’ll suffer for days as the wound will take a long time to heal.
So what in the world just happened? Well my friend, you have just run afoul of the kamaitachi, or the sickle weasel. The critters are yokai that hang around the Koshin’etsu region for the most part. They are said to resemble weasels, with sharp, sickle like claws. Accounts of their attacks vary; some claim that they attack in trios, while others claim the monsters work alone.
What they can agree on is that the sickle weasel first attacks with a strong gust of wind, or a whirlwind, knocking their victim to the ground (they only attack men, by the way). The second phase of the attack is using their sickle-like claws to cut a deep gash into the skin, and the final phrase is to apply a medicine that numbs pain and stops bleeding. The attacks happen instantaneously, with the weasel moving faster than the eye can see (which begs the question of how anyone knows what the thing looks like, but that’s another matter).
The kamaitachi appear in anime, manga, and novels. So far there don’t seem to be any modern accounts of attacks by these elusive creatures. Like most things folkloric, it seems the sickle weasel exists exclusively in the minds of those who believe in them.