I found the first book of these series to be extremely predictable at times.  I did not have that problem at all with this book.  It's a rare example of a second book that's better than the first, and the first was excellent in its own right.  I think this one was slightly less violent and bloody, but the plot was so much more gripping.  I loved this, and I can't wait to see where the next book goes.
R.F. Kuang has a unique ability to get me to worry and care about awful people.  Rin and her friends have done some really terrible things, and yet I still care so much about what happens to them.