Io Hokari runs the Bottleman Management Association—basically the governing body for the whole sport—and he's best known as the former Bottle King champion. He's also Ryou's father, and his own dad, Suezou Hokari, founded the BMA back in the day. His name is a reference to Pocari Sweat's Ion Water product, a popular Japanese sports drink brand.
Content compiled by AnimeList.moe from publicly available sources.
