As a sideline fan of BTS (like…I listen to them, and thanks to my students, I know quite a bit about the members), I didn’t learn much from reading this memoir. It’s a mix of interviews and a timeline-retelling. While it does mention “highs” and “lows” of the group, there isn't a huge amount to take away as a reader. 
It is basically a printed version of the love that the members have already put into their music and interactions. Which has its purpose! 
But, on top of that, it wasn’t necessarily translated in top quality. Many thoughts felt half-finished and better questions could have been asked.