Boss’s Death Guide - Chapter 17 - Fish Soup

The MC (Minato) is a college student who died in a plane crash and was reincarnated in a fantasy world. He was raised alone in the wilderness by his succubus mother, and now he tries to make his way as an adventurer.

When a young woman is killed in a traffic accident on her way home from work at a tax bureau, she suddenly finds herself transported to the world of the otome game she was playing the night before – but instead of the heroine, she’s been reincarnated as the bad guy! Using her knowledge of the game, “Iris” manages to avert personal disaster and decides to rebuild her life with her modern-day economic know-how. This is one mean girl who isn’t going to let her perceived reputation stop her from being a heroine!

The journey to the martial peak is a lonely, solitary and long one. In the face of adversity, you must survive and remain unyielding. Only then can you break through and continue on your journey to become the strongest. High Heaven Pavilion tests its disciples in the harshest ways to prepare them for this journey. One day the lowly sweeper Kai Yang managed to obtain a black book, setting him on the road to the peak of the martials world.

- 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