First things first this manga is definitely not for everybody as my enjoyment mainly came out of very specific personal taste.

The premise is very interesting however it is not the best thing about the manga, nor is it the main focus.
The art is also very sketchy (a personal favourite style of mine) and has nearly no refinement so first impressions of the art will most likely tell you whether you enjoy the style or not.

The point I want to focus on though is the character study aspect of the story as it is both the main focus of this manga (especially the further in you get) as well as the most interesting. Agni is a character for better or for worse is incredibly hard to get a lock on and attempting to patch together the story since it is told from his (not so reliable) point of view is the almost like a puzzle. His motives are always simple, too simple some might argue however are not predictable, as he himself is not quite sure what he wants.

Overall I like this manga a fair bit and if you are looking for something different from a typical battle shounen or fantasy manga to read this is not a bad choice.