|“||Several times you have rejected me offering my power, but now you seek my help?||”|
Raijū (雷獣, Raijū?, lit. "thunder animal or thunder beast") is the twelve-tailed demon wolf of Kagemoto Uzumaki. He is a tailed beast possessing Lightning nature, which enables him and the Jinchūriki to be quick as lightning. Kagemoto became his Jinchūriki after getting the mysterious Dōjutsu.
Note that this section was directly taken from Wikipedia.
Raijū (雷獣,"thunder animal" or "thunder beast") is a legendary creature from Japanese mythology. Its body is composed of lightning and may be in the shape of a cat, fox, weasel, or wolf. The form of a white and blue wolf (or even a wolf wrapped in lightning) is also common. It may also fly about as a ball of lightning (in fact, the creature may be an attempt to explain the phenomenon of lightning). Its cry sounds like thunder.