Short answer: Watch this. Watch it now.
Longer answer: The manga is almost entirely translated and volumized now, just waiting on the last book. This anime is great. The story is great, character design is great, and it's just awesome. My only wish is that the last few episodes stayed true to the manga. It's apparent they rushed it to kill off the series, even if you haven't read the books. Other than that, it's just a badass show with badass chicks doing badass things. Raki can seem like a whiny bitch, (and he is), but he's actually a good character later!
If you like blood, and nice art, or even anime in general, try this. This was the first anime I got my girlfriend to watch and actually really love!