I hadn't read the novels when I first watched the end of the anime. I actually wasn't into the fandom at all yet, because I was sort of actively trying to avoid being spoiled. (I realize now that this was perhaps silly, since everything would have made a LOT more sense had I known more of the story :P) But yeah, I was actually confused at first as to why people were so upset, because honestly, with the ending as it's prepared in the anime, I don't think I really got that Nezumi was gone gone at the end. XD;; I don't know if I would have, either, had I not immediately read a bunch of fan reactions, and then promptly read all the novel summaries myself so that I knew what everyone was going on about. ;) So yeah, my very first reaction was of confusion, mostly, about pretty much everything that happened in that last episode.

And then after I read the novel summaries, I was really, really sad once I realized the implication was that Nezumi was gone, perhaps for many years, at which point I proceeded to read a ton of fix-it fic. ;)