One of the most down-to-earth person of the Blade Children; Ryouko is a clever and athletic person, probably the most athletic of the Blade Children. She is a natural-born runner and can outrace almost anyone. She is a childhood friend of Kousuke Asazuki and, unlike the other Blade Children, she despises killing. She dislikes Eyes Rutherford due to past issues and cares deeply for Kousuke, though she has a tendency to use him as a punching bag and make him buy her food. Her past is relatively unknown, though it is hinted that something traumatizing happened while Kousuke and Eyes were present. She is relutantly brought back into the conflict of the Blade Children by Eyes after losing to him in a simple game of dodge ball. She honors their deal to join with the rest of the Blade Children, with only one condition: she will not kill anyone.
She is still with Kousuke and hopes to run in the Olympics.