A Certain Magical Index

A Certain Magical Index (とある魔術の禁書目録インデックス) is a Japanese light novel series written by Kazuma Kamachi and illustrated by Kiyotaka Haimura, which has been published by ASCII Media Works under their Dengeki Bunko imprint since April 2004. It has consistently been a bestseller since it began publication and is split into two series, an "Old Testament" and a "New Testament."