Kuriba Ryouko

Kuriba Ryouko (操歯涼子 (くりばりょうこ)) is a student of School District 20's Shinshikimi Middle School and the creator of Indian Poker.

Appearance
Kuriba Ryouko has vertically striped hair, alternating between light and dark from a dark stripe at the middle of her frontal fringe.

Background
When she was little, Ryouko was caught in a building collapse and only survived due to a lung transplant from her mother. Her mother had a weak body even before the incident and was far from healthy afterwards. Ryouko subsequently dedicated herself to research in Academy City in order to learn the cyborg techniques needed for her mother to make a recovery. However by the time she produced results, her mother collapsed. Having caught an infection from, her body was at its limit. The advance of the infection was delayed by drugs but doctors only gave her a year or two at most to life. Ryouko needed to develop cyborg replacements for her mother's infected parts, but was faced with an overwhelming lack of data for development and the difficulty of gathering data on all of the many body parts needed for the treatment.

In order to gather this data in the time she had left, Ryouko volunteered herself for a cyborg experiment run by the institution she was working with, in which her body was split in two and the missing parts replaced with machines to create two separate cyborgs. Acting as both observer and specimen, Ryouko planned to use the experiment to gather data on every part of the body. After a year living apart, the two Ryoukos were recombined into one, with no split personalities or rejection, and retaining the memories of the time split apart. While Ryouko wished to test the compatibility between the cyborg technology and the human body, the institution hoped to observe a possible side-effect - the creation of a "soul".

Ryouko subsequently learned of her doppelganger and warned the scientists of the potential risks, but she was ignored. At some point afterwards, in order to find a solution to the doppelganger problem, she created the Indian Poker cards which enabled people to record and view dreams, and distributed the method to produce them.

Dream Ranker Arc
Ryouko first appears in a Indian Poker card that Misaka Mikoto was using as she was searching for the Bust Upper card. Seemingly speaking to Mikoto directly, she speaks cryptically of the future and that there is a threat that not only Mikoto cannot ignore, but also a threat that could lead to another one if Mikoto eliminates it. Before Mikoto could confront her, she appears to split into two.

Mikoto later meets two "Ryoukos" for the first time after the Electromaster was asked by Shokuhou Misaki to investigate on Ryouko's background. The first Ryouko, which was entirely mechanical, escaped from her facility by jumping from the topmost floor (and surviving). Meanwhile, the original Ryouko is later tracked down by Mikoto in an apartment complex with the help of Misaki. Although hesitant to cooperate at first, the original Ryouko eventually agrees to explain her involvement with the "soul creation" experiment and the development of the Indian Poker cards.

Abilities
Ryouko's exact capabilities aren't fully known, however she is knowledgeable and intelligent enough to have devised a number of the technologies which were used for her cyborg body, as well as countermeasures against them. She was also capable of devising multiple methods for Indian Poker from readily obtainable tools.