The first half of this show was awesome -- hardcore murderers, creative mysterious, likeable characters, and light humor the take the edge off, too. Through and through, the art and music of this show were amazing, but unfortunately, out of nowhere, it went from being a nice gruesome mystery show, chock full of tasteful references to classic detective tropes, to an overly pretentious supernatural romance schlick that was trying way too hard... to be the next Steins;Gate? Death Note? who knows? and getting nothing accomplished.
If you want to watch the first 4 eps, go ahead, but stop there. The flat characters, non-mysteries, and pretentious empty symbolism make for a weak combination.