I'll admit it right now. I struggled to finish this anime. The characters I enjoyed, but didn't love. The plot (what plot?) was non-existent until the 15th episode, the setting and general storyline got boring, and after a while I just didn't care any more.
Now, although I did not like it, I would not call it a bad anime. It does have a level of drive that you don't really notice until you realize, "wow, I finished this after all?" It does not have much substance, but the little it does have it works with well and makes sure to tie up all the loose ends. WHR is well-structured.
Character-wise, as mentioned before, I liked them but didn't love them. It goes back to the setting. They do the same thing while you slowly learn more about them, and though the base concept is definitely interesting in its own way, it was not enough to keep me enthralled.
For people who are looking for something action-filled, and creepy and gory, look elsewhere I say. While it does have quite a bit of action, and a few creepy scenes here and there, gore is completely absent (which, in my opinion, is not a bad thing). WHR takes itself seriously in its level of what's needed is there, and what would be excess stays absent. Deaths are also very subtle, not dumbed down in the "his throat was slit why is there no blood?" sense, but just hinted at enough to get what happened.
WHR's small substance of a story worked for and against it. To some it might be for, whereas you can immerse and follow easier if you love the characters. But for others, such as myself, it lacked the quirks that make a story worth following. It was all story without plot and without the character of fiction.