Gamakichi

Gamakichi is the son of Gamabunta, and the older brother of Gamatatsu. Typically, Naruto summons Gamakichi when he doesn't have access to his Demon Fox chakra. Gamakichi was puporsely summoned by Jiraya during one of the Anime's filler arcs and was told to search one of Orochimaru's hideout, considering he's potentially small, Gamakichi was able to search the hideout without getting caught. Gamakichi only "plays" with someone if the one who summons him gives him a treat.