Ruui

Ruui is a dead samurai whose spirit is unleashed in the trial of the Rage Blitzen Katana. His legacy was that that lived on in an age that was before Tojijoro. He has been in legendary fights, including with Tojijoro. He is believed to be partly responsible for the time that the Boei No Chi was founded, and he may have been a former Boei No Chi member.

• In Episode 13, Rage Blitzen Katana, it is depicted as a red spirit that is full of rage, that represents the hatred of the Jiangsu.

• Its Katana is special because it can channel any rage into Chi power that is able to strengthen the impact of its blows.