Futsunushi

In Japanese mythology, Futsunushi (経津主神, Futsunushi no kami) is a kami of swords, thus his shinto priests are supposed to always wear Nihintō with them, at least in the shrine. He is a general of Amaterasu along with Takemikazuchi. As the god of Katori shrine and god of martial arts, Katori Shintō-ryū adepts make a solemn oath when they join the school.