Spin-off series about the everyday life of the members of the Armed Detective Agency and the Port Mafia.

Having been kicked out of the orphanage, a despairing young man by the name of Atsushi Nakajima rescues a strange man from a suicide attempt--Osamu Dazai. Turns out that Dazai is part of an armed-detective agency staffed by individuals whose supernatural powers take on a literary bent!

(Source: Yen Press)

From the MangaHelpers website:

Siblings Ayane and Kurumi have unique supernatural powers known as Ghosts, each with their own unique rating that designates their powers. Ayane has a score of 7, while Kurumi has a score of 11. Ayane's ability allows her to control shoe laces, while Kurumi can form contracts with objects, which allow her to control them.

Ayane feels severely inferior to her sister, but will she be able to prove herself against the other Ghost-bearers in combat? [DrCoke]

The story begins with an attack on humanity by giant indestructible monsters named "Enemies". The Enemies drive humanity to the brink of extinction... but the one to save the world from the depths of hell is a lone boy!