Manshuu Ahen Squad

In the corrupt, conflict-ridden Japanese puppet state of Manchukuo, the illegal opium trade is a perilous path to quick riches—or a swift death. Desperate to save his doomed family, the young Isamu Higata seizes a dangerous opportunity, using his botanical expertise to make mind-blowing opium in hopes of cashing in. But when sinister gangs and the oppressive state catch wind of his operation, Isamu is thrust deeper and deeper into a treacherous world of deceit and depravity to protect himself and those he loves.

(Source: Kodansha USA)