A certain scientific railgun. Vol. 2 - Kazuma Kamachi

Meet Mikoto Misaka, the third most powerful Level 5 esper in Academy City. Together with her best friend Kuroko Shirai and the other members of Judgment, a student-run law enforcement agency, Mikoto delves deep into the dark heart of the scientific sprawl she calls home, and uncovers secrets she wishes she hadn't!
As word of the all-powerful "Level Upper" begins to spread, Harumi Kiyama and her team of medical experts are called in to investigate a sudden rash of comatose patients. While the medical community refuses to believe in the existence of the "Level Upper," Mikoto Misaka and her friends suspect otherwise.