Ore no Imouto to Railgun Collaboration Project!

The Ore no Imouto to Railgun Collaboration Project! (俺の妹と超電磁砲のコラボプロジェクト！), translated as My Little Sister and 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 Kamachi Kazuma.

Background
Although not his first foray into fiction related to the Toaru Majutsu no Index universe, with his short story, Toaru Bushitsu no Fanatic (とある部室の映像中毒(ファナティック)), translated as A Certain Clubroom's Fanatic appearing in Pseudepigrapha Railgun alongside Toaru Jihanki no Fanfare, where the characters of Index are treated as fictional characters, this story shows that both stories occur in the same universe.

It was first announced the Machi Asobi event on May 5, 2013, and the first story was published on Dengeki Bunko's page on the Nico Nico service. The first story was published on June 14 with upcoming stories being published every Friday Pacific Standard Time.

After Fushimi Tsukasa finished his half of the story, Kamachi Kazuma then started his half on September 5, 2013, titled Toaru Majutsu no Index Gaiden Toaru Kagaku no Railgun Ore no Mikoto ga Konna ni Abare Mawaru Wake Ga Nai (とある魔術の禁書目録外伝　とある科学の超電磁砲『俺の“みこうと”がこんなに暴れ回るわけがない』), translated as A Certain Magical Index Side Story A Certain Scientific Railgun "My Mikoto Can't Be This Berserk"

Synopsis
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...!?