Mikoto Misaka

She is the third ranked Level 5 esper in Academy City, and has been nicknamed Railgun due to her signature move. Kamijou Touma coined the nickname Biri-Biri (ビリビリ, Biri-Biri) (a Japanese onomatopoeia imitating the sound of electricity), while in the English dub she is referred to as "Bug Zapper" (or more usually, simply "Zapper"), and whenever the two meet, he usually calls her that, even after his amnesia.