User with this ability either is or can transform into a kamaitachi, Japanese yōkai appearing as weasels with razor sharp nails shape and length of long sickles. These weasels travel on whirlwinds to move at high-speed, slashing their victims with their sickles to inflict deep wounds. They move at such speed that they appear as the wind itself. They're essentially the personification of the pain felt during a bitterly cold wind.