I watched the Netflix movie before I read this, because some amazing fan out there took the time to translate the whole book into English specifically after they watched the movie themselves. The copy of the translation got taken down, but not before I was able to read it in its entirety.
The movie ripped my heart out and tore it into a million tiny pieces, so I was curious to see how the source material fared. It's one of the most faithful book to screen adaptations I've ever seen, only a few scant details were changed during production of the movie from what I could tell. All the plot threads and emotional beats were present, and I enjoyed it a great deal.
This is not a happy story, even with its bursts of lightheartedness, but it is an important story and at its core, a version of reality that many people had to endure: the oppression, the hiding, the inner turmoil, the societal pressures. Just a taste is presented as to what it would be like to live in A-han and Birdy's shoes, and it's not pretty.
I must say, the cherry on top of this whole cake is the song that was created as the theme song for the film (and played during what I consider to be the climax aka the part that makes me cry my eyes out); it's such a beautiful and haunting number and really elevated the emotional atmosphere of the already-charged scene.
It's not very long at all, less than 200 pages according to the Kindle edition, but nonetheless it manages to pack a serious punch and leave a lasting impression on your heart.