I really like this anime. The storyline is great (although the anime's ending is pretty inconclusive - for a more satisfying ending the manga is recommended!), and the characters and mysteries are what make the show interesting and riveting.
The animation is good, the soundtrack is pretty much perfect and the episodes as standalones are great at sucking you in to keep watching. I just wish there were more episodes to conclude the overarching mystery rather than just solve a few plot twists.
That said, the episodes are still good fun to watch. The characters are interesting as none are inherently good or inherently bad (this especially applies to the Blade Children), and this morally grey area makes for a good ground to think.
If you like detectives, mysteries and creative murder-centric plots, I cannot recommend this enough!