Kuroko Shirai is a character from the light novel "A Certain Magical Index" and its derivative works. She is a first-year student at Tokiwadai Middle School, a member of the disciplinary committee's 177th activity branch, a Level 4 powerful user, with the ability "Teleporter." She is one of the heroines in the spin-off "Scientific Railgun." She is slightly shorter and has brown hair in twin ponytails. Because she has natural curls, she often goes to the Sakashima Michibata beauty salon to fix the ends and straighten her hair. Due to school regulations, even outside school, in the dormitory, and during winter and summer breaks, students wear uniforms and three-fold socks, with a somewhat traditional appearance being their most distinctive feature. The belt tied at the base of her thigh was loaded with darts, and metal arrows for one-handed crossbows were inserted. This was her ultimate move, which allowed her to instantly move metal arrows onto targets using spatial movement. She usually behaves very "ladylike," speaking with a distinctive ladylike tone ending sentences with "~ですの (yes o)".

Kuroko Shirai is Mikoto Misaka's junior and roommate. She became a disciplinary committee member in fifth grade, relentlessly fighting criminals, and is rumored to be the "most evil spatial mobility among the committee members." She is kind-hearted, with a strong sense of responsibility and justice, often showing a maturity beyond her years, and takes pride in maintaining public order as a disciplinary committee member. However, she is usually frivolous toward Mikoto, often stealing her lingerie, collecting under the bed a collection including underwear and secretly photographing Mikoto Misaka, and likes to wear various minimally fabricated lingerie to "seduce" Mikoto. In reality, because she needs to fully concentrate when using her abilities, comfort is the primary condition for choosing lingerie.