Kama (カマ Kama) is the leader of the Garou Knights, the most powerful executioners of Fiore. Kama carries around Double Scythes with peculiar hand-like extensions from the opposite side of the blade. He carries these on his back with the handles crossed and are deadly in their own right.
In the anime, his name remained unknown, however, Mirajane provided a name for him, Kama, to which Lucy referred to as a term meaning "sickle".
(Source: Fairy Tail Wikia)