Very interesting, creepy anime, but difficult to get. The plot is told differently every few episodes. I'm still not sure what the purpose of doing so was supposed to accomplish. Nevertheless, it was still awesome to watch.

my rating is for season 01 only. s02 is ok, the rest just spirals into a...i dont even know what, an average fan service-y piece of shite if i were hard-pressed to put it into words. especially the specials. s01 is really a sight to behold. if you are thinking in the first 2 or 3 eps that this is an average harem type anime, please just stick with it. i promise it will pay off.
some of the specials can be enjoyed if they are viewed as a parody. i dont know if they were intended as such but if i took them seriously i would have thrown something at my tv.
this is about as horror as anime gets. so if you are looking for good horror anime s01 of this is essential viewing. after the first few arcs it does get a little same-y, but i think every arc has something that really shocked me.
a must watch if your looking for something a little different.