The Ore no Imouto to Railgun Collaboration Project! is a crossover fiction web series penned by Ore no Imouto ga Konna ni Kawaii Wake ga Nai author Fushimi Tsukasa and Toaru Majutsu no Index author Kamachi Kazuma. ... more>>

One day Kirino is offered the job of having a live talk over Niconico Live with Mikoto Misaka a Level 5 esper from Academy City. "Maybe she'll introduce me to her little sisters if we get along.. ehehehe," so saying, she immediately accepts the job and visits the Niconico main office with Kyousuke but...!? <<less

Both short stories both take place in a world where people known as Killer Demons have each mastered a specific form of killing. Each story follows a different character's encounter with one of those Killer Demons.... more>>

Killer Queen and Deep End was originally submitted for but did not win a Dengeki contest before Toaru Majutsu no Index was published. It was later published in 2004 in response to Index's popularity. Killer Device and Never End was written and published in 2005 due to the popularity of the first story. <<less

The story takes place in the near future. Money (Game) Master is the world's biggest VR online game. It is an open world game with no levels and no quests, the only goal for players (known as Dealers) is to make money. All sorts of illegal actions like violence and theft are allowed in the pursuit of Snow, the game's virtual currency. Due to the game's massive popularity, Snow has a significant influence in the real world, thus making the game's conflicts part of the global economy. Each Dealer is partnered with a Magisterus, a female support AI modelled after a supernatural creature, which acts as their guide and support.... more>>

Kaname Suou, the main protagonist is a famous Dealer, with a succubus-type Magisterus is called Tselika. Formerly part of a famous team known as Called Game, Kaname undertakes a mission involving the Inheritance, a set of cheat weapons created by a Dealer known as Criminal AO that can break the game's balance, and with it, the world's economy. <<less

In Academy City, magic and science coexist in an unwavering power struggle. Toma Kamijo, an academically-challenged student in Academy City, wields the power of the... more>> Imagine Breaker in his right hand, which allows him to completely negate all supernatural powers – as well as his own luck. When he happens upon a mysterious nun named Index, whose mind has been implanted with the Index Librorum Prohibitorum – 103,000 ancient texts banned by the Church – Toma’s luck is about to be pushed to its limits when he finds himself in the middle of a war he never expected! <<less

Volume 1 (Set between volumes 13 and 14)
A series of short stories set before the events of volume fourteen including how Team GROUP was formed.... more>>

Volume 2 (Set between volumes 16 and 17)
A series of short stories including two separate meetings between Touma's and Mikoto's parents, two tales involving two of the Level 5s of Academy City, and other funny stories involving some of the characters. <<less

A series of short stories in the world of Toaru Majutsu no Index organized into chapters featuring Kanzaki Kaori as the protagonist, going around the world and space doing missions for the Church of Necessary Evil, however, there is more than meets the eye as each incident is connected.... more>>

One chapter was bundled with each limited edition release of the Toaru Kagaku no Railgun anime DVD and BDs, with all of them together being equivalent to a single normal Toaru Majutsu no Index volume <<less