This is the hardest book in the series for me to reread, probably because the concentration camp imagery seems like a reflection of the Holocaust. The other books have terrible things happening, yes, but in a far-future dystopian way that's much harder for me to see paralleling the real world. Also, there's the assisted suicide of a Certain Character, which never fails to irk me for being so completely out
of character. And not one--not two--but three! sexual encounters, all full of piscine allusions and over-the-top descriptions of the main character's virility.
Still strangely compelling, though. Also necessary for understanding the rest of the series.