Juubey
Described as a fairy, but very likely an Incubator, he was the Pleiades Saints's contractor. He is particularly notable for being able to clean their Soul Gems by his own, relieving the girls of the need to compete for Grief Seeds. He was originally one of Kyubey's bodies that the Pleiades Saints' altered with their various magics after learning the truth of the Puella Magi system. They made the real Kyubey invisible to the world, but realizing the Incubators' usefulness as an unlimited Soul Gem purifier, 'created' Juubey as a false Incubator under their control. His name is a pun on Kyuubey's, as "kyuu" can be read as 9 in Japanese, just as "juu" can be read as 10. (Source: Puella Magi Wikia)