First of all i would like to warn others that this anime does not have have a very good art style, especially the characters' eyes and the art style is not what you would expect from an anime with such a high rating.
However, Art is not the only major factor in reviewing this Anime. This anime has awesome story and i think all the characters are unique and each have their own story, even for some of the "bad" guys. There is however some imperfection to this anime as there is very little action scenes in each episode. I would love to have more epic actions and battles.
This anime also carries a lot of deep messages across such as facing your past and shortcomings. Even the 'bad guys' displayed loyalty, friendship and love and it was actually quite touching. Watch it for the story.