Kekkai Sensen (manga)

Blood Blockade Battlefront (血界戦線, Kekkai Sensen) is a Japanese manga series written and illustrated by  Yasuhiro Nightow.

Plot
Three years ago, a gateway between Earth and the Beyond opened over the city of New York. In one terrible night, New York was destroyed and rebuilt, trapping New Yorkers and extradimentional creatures alike in an impenetrable bubble. Now, New York has been rechristened Hellsalem's Lot, a paranormal melting pot where magic and madness dwell alongside the mundane, where every form of human vermin gathers to exploit otherworldly assets for earthly profit. Now someone is threatening to breach the bubble and release Hellsalem's Lot’s horrors, but the mysterious super agents of Libra fight to prevent the unthinkable.

History
The manga started as a oneshot published in Issue 2008-06 of Jump SQ. Later it became a 3 chapter mini-series published in the same magazine from Issue 2009-02 to 2009-04. In October 2009, it received a sequel chapter released in the Jump SQ.M vol.002 Issue. In the beginning of 2010, the 4 chapters were combined as Volume 1. In May 2010 the manga started serialization in the new magazine Jump SQ.19 which is released once each season (4 times per year). In 2012 the Jump SQ.19 magazine became bi-monthly and started to come out each 2nd month (6 times per year).

An 12-episode anime adaptation was announced in 2014 and started in April 2015, produced by Bones. A second season of 12 episodes was aired from October to December in 2017.

In the early 2015, the Jump SQ.19 spin-off magazine was disbanded and new Jump SQ spin-off magazine would start on its place later that year, where Kekkai Sensen would continue. In the mean time, Kekkai Sensen continued in Jump SQ issues 2015-05 & 06, and also received a special chapter in Shonen Jump 2015-20 issue to commercialize it's anime start. In July 2015, Shueisha announced the replacement magazine would be seasonal (4 times a year) and be called Jump SQ.Crown, the first issue came out on July 17 with a new chapter though under the new sequel title called Kekkai Sensen Back 2 Back. In January 2018, Jump SQ.Crown ceased publication with its replacement called Jump SQ. Rise beginning in April the same year; there was no changes to the manga.

The manga was published in English by Dark Horse Comics, but most volumes are currently out of print and without a digital release available.

Oneshot

 * Oneshot