Like my others reviews I'll try to be fast. Very good anime, it has action, drama, gore, good background story and a good character development. For the ones looking for story, it has a great story line, a great background story and a great character history. For the ones looking for a cute anime: This is not your kind of anime. This is a great anime beacause everything on it works, the sinergy between all the characters, the background story, the action/violence when it's necesary, all seasoned with an excellent soundtrack. The only thing I didn't enjoy was the art. But it's a minor fact at the end of theseries.
I highly recomend this anime. 8/10