The main character is actually a sniper. Alice is a malfunctioning android he uses as bait, to lure bandits into the open before killing them. Alice looks like a teenage girl. Jiro's manga tend to be very psychologically difficult, all are about bad things happening to bad people, living in societies that encourage human suffering. His manga usually have a fair amount of nudity and violence.
Oh wow, both sound very cool. Its interesting that the main character is a man who plays the role of Alice. How sadistic is sadistic? Shinsekai sounds a bit like Nausicaa.