Raiden Kurosora

Raiden Kurosora (電 黒空, Kurosora Raiden, lit. "The Dark Heavens Lightning") is a Raijuu, which is a race of animals whom according to legend is made out of lightning. He came from the sky and met Shinime. They became friends due to them bonding over missions. Raiden got named by him, so Raiden protected Shinime until he learn magics of his own.