A Railgun in Fairy Tail Book 2: Dragons

Academy City. A city comprised of colleges, high schools, middle schools, and elementary schools all designed to develop and create espers. However there is a darker side to this City. After their battle with Hydra Head ripped them from the dimension of magic, Mikoto Misaka finds herself home, and her fellow Fairy Tail guild members find themselves in an unfamiliar world of science. As Mikoto's friends try to adjust to this new world, Natsu finds himself meeting a man named Stiyl Magnus, a magician from an organization called Necessarius. Soon the Fairy Tail mages find themselves wrapped up in a new kind of magic with a strange little girl named Index at the center. Now, If Mikoto and her friends wish to survive the coming storm, they must battle a newly resurrected from the dead Grimoire Heart. The problem is.......Grimoire Heart aren't the only ones after Index.