Online game: God-level Assassin, I Am the Shadow. - Chapter 130 - :Mythical Level, The Shadow of Slaughter!

Floren, the most renowned realm of all realms, yet forgotten by all. The soul of a person from Earth accidentally crashed into this unexplored realm, ending up in a dragon egg. Transforming into a crimson dragon with the mindset of a human, Claudius was different from other dragons. He only wished to live an easy life, enjoying his lifespan of thousands of years to its fullest. However, the world is not such a forgiving place, dragging Claudius into countless struggles and death battles. Is it really possible to live a leisurely life?!

- Description from Novelupdates

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.

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

In the legends that were told, ten thousand years ago the twelve demon kings wreaked havoc upon the world, almost completely destroying it. Ten thousand years later, the late arriving Bella discovered that she had been screwed over by her reincarnation, the ranks of the Saviors are already filled and she has to change teams in order to pass the days. Having her gender changed into a beautiful girl… she endured that, not being able to join the righteous side and obtain cheat abilities… she endured, but what she could not endure, was that the world that she had transmigrated to was toxic beyond belief. No one here does their rightful jobs properly, be they heroes, demon kings, or creator gods… in fact, Bella felt as if they all had also started with the wrong faction!