Toaru Kagaku no Railgun (manga)

To Aru Kagaku no Railgun (とある科学の超電磁砲（レールガン, To Aru Kagaku no Choudenjibou lit. A Certain Scientific Railgun) is a side story of To Aru Majutsu no Index. It started serialization in Dengeki Daioh in May 2007. The story tells of the events before and during the time of the novels from a different perspective from the main character, Mikoto Misaka and her friends.