Sanada's twin, along with his brother Sanada Yukio, are two of Shun's group's contrincants on the other side of the line while playing Shouben kouzou. He is one of the people who are able to ascend to Urashima Tarou's castle, however he is killed when he picks up the X from a bowl Tarou gave them.
Despite being twins, he is more level-headed and serious compared to his brother. According to Yukio, he was always bossing Yukio around and telling him what to do. His first name is never mentioned in the series.