A Goodreads user asked:
Would I understand the story if I just read this book? I bought it at a charity shop and didn't know which number in a series it was (I just saw RICHELLE MEAD and hoped it was the first)
Cristina @Angie is right this is the last book in the series. To answer your question..Most people would say that you can understand the story by reading only the last volume. It's nothing wrong with that but I would totally go for the whole series as I find it very captivating.