Livingstone is a collaboration manga between Maekawa Tomohiro, the author and Kataoka Jinsei, the artist. You might have known Kataoka's work from before: Eureka Seven.
First lemme explain what is the 'living-stone'. Living stone is the soul stone of a human being, which weight approximately 30 grams according to Professor Duncan who did an experiment to determine the weight of human soul.
This manga tells a story of two guys, Shozo Sakurai and Amano. Their job is to hunt and prevent people from their unplanned/unnatural death or otherwise to recover the "living-stone". To make sure that the next person will not suffers the same fate as the person who is about to die, because "unexpected death" will damage a human soul, they have to ensure that the living stone will not be in pieces. In other words, their job is to "save" the livingstone, preserving its proper shape and "kill" the body that's left behind in this world.
Besides that, they also have to clean the stain where "unexpected death" occurred and collect the pieces of livingstone. This is because the place where those death happened, if not cleaned, will carry negative energy that will lead to other unplanned accidents.
Sakurai is the compassionate person between the two. He will strive his best to save the victim. The irony is he always ends up doing the killing part which takes quite a toll on himself. Sakurai has the power to see the memory of the soul once he has the soul stone in his hand. It was a pain and most often than not, a gruesome experience.
Amano is the polar opporsite of Sakurai because he has no soul to begin with. He has no memories or feelings either which usually gets him into trouble. He has a stone installed inside of him that attracts the living stone. Amano lives solely to do his job and has the power to see the stains. He is also kinda immortal.
Amano and Sakurai provide a comedic relief once in a while with their antics that makes me enjoy this manga. Amano said some of the funniest lines with Sakurai delivering the punch lines. Definitely not going to put this one on hold :3