If tl:dr : Excellent story get your hands on it and start reading.

So I start reading this manga a couple of years ago (like 2006) because I thought the art was rad. And not only does it turns out the story is also excellent, so are the themes. It's a good mix of sci-fi, fantasy and historical manga that is revealed (a lot later on) to double as a mysterypolice story.

One of the things that I loved the most is that not one of the character feels superfluous. They all have a backstory to explain their motivations and why they act as they do. It's one of the things I love about this manga. Not one vilain is truly evil, they all try to protect what they cherish and all have reasonable utter-motive.
#aka Bonten and Tsuyukusa, the Princess or name it...
Life is just harsh in medieval Japan and everybody is tied to the choices and consequences of their acts.

I also love quite much how the author use chibi art to cut some tense situations in the manga too, and how queer some character act sometimes! And As someone else said some blanks are left in some scenes that make you wonder what certain character might be doing but it's usually discovered later on.

The only thing that KILLS me is how slow the production of this manga is.

Like serisouly 108 chapters in 13 years