It's a story about the fear of growing up, the good/bad and the journey to find ourselves. It has a lot of symbolism and references to Jung's Archetypes so I recommend to read a little bit about Jung (and The Bible) for better understanding of this book.
The translation is very easy to follow compared with anothers I checked, then if you aren't an English native speaker, you could read this edition without problems.
About the Wings album. The first five chapters are the ones that are more relationed with the short films, specially Jungkook's one, but is not an easy book to be sincere.
I enjoyed it, a lot.