Kamaitachi
The Kamaitachi is a form of Yokai from Japanese myth. Its name translates to “sickle weasel” and is often depicted as weasels holding tiny sickles. They work together in groups of three. The first Kamaitachi slashes at the victim to knock them down, the second one slashes the body before it even reaches the ground, and the third then magically heals the wound, spilling almost no blood. Attacks from the Kamaitachi often happen in swamps, and sometimes those who have been attacked will become incredibly sick and then die.
Citations:
Maberry, Jonathan. Vampire Universe: The Dark World of Supernatural Beings That Haunt Us, Hunt Us, and Hunger for Us. United States, Kensington Publishing Corporation, 2006.