No.6 recommend

No.6 is a novel written by Atsuko Asano. Also there are a comic version of it. This manga is 

introduced by my friend to me. It is about life and death. Two main characters are Shion (seaaster) and Nezumi (Rat). They have a strong bond throughout their journey after facing lots of challenge. That they had change the fate of their city. The story's scene is attractive, and the angle that used in the scene is powerful. 

To No.6