No Guns Life

No Guns Life (ノー・ガンズ・ライフ, Nō Ganzu Raifu) is a Japanese manga series written and illustrated by KARASUMA Tasuku. No Guns Life oneshot was published in the 2013-08 Issue of Ultra Jump under the "Ultra Collection" label. The next year, a second oneshot done in 2 parts were published in Issue 2014-04 and 2014-05 under the same label. Later the oneshot turned into series and started from 2014-10 Issue of Ultra Jump.

Plot
After the war, there are many "Extends" in the city, people whose bodies were modified to make them into dangerous weapons. Inui Juuzou is one of them, and he has no memories of his life and body before his head was transformed into a gun. Strangely enough, his head-gun is designed so that only someone behind him can pull the trigger. Juuzou makes a living by taking on cases involving Extends in the city, and he is assisted by Mary, an intelligent young woman that he has taken under his protection.