Toaru Majutsu no Index SS: Kanzaki

Toaru Majutsu no Index SS: Kanzaki summary:

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 s.p.a.ce doing missions for the Church of Necessary Evil, however, there is more than meets the eye as each incident is connected.
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