Gato

Gato is a prominent member of the Dark Guild, Naked Mummy. He has a strange tendency to repeat sentences twice, with the second following the first after some seconds, without realizing it, something about which he’s always informed by Zato.

Gato is first shown in Naked Mummy's headquarters, brutalizing one of their comrades for not having brought back any money, having been defeated by Lucy Heartfilia while robbing the LOVE & LUCKY merchant guild.

(Source: Fairy Tail Wikia)