Kuroko Shirai

Kuroko Shirai is a character in the A Certain Magical Index and A Certain Scientific Railgun franchises. She is the roommate of Misaka Mikoto at Tokiwadai Academy, who she has a love interest in and usually refers to as "onee-sama" (translated as "sissy" in the English dub). Kuroko is a Level 4 esper with the ability to teleport herself or objects she touches under a total weight of approximately 130–137 kilograms (287–302 pounds) to anywhere within a radius of around 81–85 meters (266–279 feet), but her ability it requires an amount of concentration for successful execution. She is a member of the student-run paramilitary and law enforcement group Judgment and generally carries a strap of nails around her thighs, which she uses during her work to pin down enemies.

She is on the constant lookout for a chance to get physically intimate with Misaka Mikoto, which often results in her being electrocuted because of the latter character's electricity powers. She gets jealous of other people who have gotten Mikoto's attention, in particular Tōma Kamijo. Kuroko officially debuts in the eighth volume of A Certain Magical Index when she investigates a robbery of the remnants of the orbital supercomputer Tree Diagram and discovers Mikoto's involvement in the incident. She gets injured by Awaki Musujime, another esper who uses teleportation powers, during their fight in a restaurant, but she is later saved by Tōma and Mikoto before Awaki can unleash an enormous teleported mass on her. After the events surrounding the Tree Diagram, Kuroko is confined to a wheelchair for some time because of the injuries she sustained from the battle. In A Certain Magical Index: Genesis Testament, Kuroko works with Academy City's non-student, professional law enforcement agency Anti-Skill to apprehend the members of the dark side organization during Operation Handcuffs and later teams up with Tōma, Alice Anotherbible, and Yōen Hanatsuyu to stop the rampage of Frillsand #G following the conclusion of the operation.

She is voiced by Satomi Arai in the Japanese version of both anime series and by Alison Viktorin in the dubbed English-language versions.

In other media

Kuroko is a playable character in the fighting video game Dengeki Bunko Fighting Climax Ignition, in addition to another character from A Certain Scientific Railgun, Kazari Uiharu (who is a non-player character that assists Kuroko).