I believe this is a sadly underrated anime. It certainly has its faults, but for me the positives outweigh the negatives by far. I've divided this review into the main points which were good and those that were not so good.
The good:
-The premise/idea of the story/ world building... (the Jin-Rou or human wolves is one of my favorite themes, the creativity seen in the order of the Ookami faith is good, the effect of the hassaku scent is interesting, the idea of mitsu and kamibito and how they have learned to exist in a human world is a fine concept, etc.)
-The voice acting is good and features a variety of seiyuu that I LOVE, including Kobayashi Yuu (who I think does a god job playing pre-teen boys), Katou Emiri (who I enjoyed most for playing Kyubey in Madoka Magica), Okamoto Nobuhiko (who does some crazy characters like Rin from Blue Exorcist and Karma from Assassination Classroom), Gotou Yuuko (who played Madoka's mom and also Asahina from Haruhi Suzumiya), and Fujiwara Keijuu (who's been in too many anime for me to pick out a favorite.)
-The OST is astounding. The opening song and ending song are both beautiful, catchy, and pretty easy to sing along with. The scores and instrumentals used throughout the anime are also some of my favorites.
-A strong-willed main female lead (Kushinada Nemuru), capable of fighting and killing but actually "good" at heart with a strong sense of duty.
The bad:
-The animation would have been fine if this were a 2005ish anime, but it was in fact made in 2010, so naturally people expected better and more detailed art by this time. It's not hideous or anything-- I think it's got cute character designs-- but it's cheap.
-A main male lead (Kuzumi) who is not convincing as a 16 year-old boy and grates on the nerves of many viewers. He's not very bright (can't understand the "mystery" unless it's clearly spelled out), he gets scared very easily, he rarely makes any effort at self-defense, and he's just kind of "delicate." I don't really mind characters like this because I like lead males with a sense of vulnerability to them, but this show went a little overboard with it. However, if you watch the anime thinking of Kuzumi as a 10-13 year-old boy raised in the city his whole life, his character is a LOT more believable and understandable.
-Insufficient discussion/fleshing out of psychology, the act of killing, and how Kushinada could be construed as sociopathic.