Once you get past the glaring flaws that I completely overlooked (mentioned by the great Tamerlane in the regular comments), this manga has a lot of sheer humanity behind it, sheer human greed, leading to the imprisonment, slaughter, and selling of humans, much like how humans themselves did things back in the days of chattel slavery, but thats a topic for another time, the sheer human fear and will to live of some characters, and the sheer human emotions, from the silent empathy from hiroto, to the sheer lust and hate from two face guy.