As with any of my light novel reviews of this series, I will begin with a location to read the English localization for yourself, given that at the time of writing this there is no official translation that can be purchased. https://archive.org/details/manga_Jojos_Bizarre_Adventure_Over_Heaven Also, it should be noted that there was somewhat of a pause for my reading of this book, as I began reading it as I would retread my way through the Stardust Crusaders manga (I had already seen the anime in its entirety), I discovered that a significant portion of this book is in reference to plot regarding as well as the main antagonistof Part 6: Stone Ocean. Therefore, I would recommend (from experience) reading this as side-material after having already progressed through the entirety of the main Jojo canon, Parts 1-6.

As for the plot, it was nothing mind-blowing, but an interesting read. It is in a diary format, in very many short, digestible chapters. It is from the perspective of Dio who is using the notebook to jot down various thoughts. Some of it is his history with Jonathan, some of it is his discussions with Pucci about "Heaven", and along we way we make note of where the Stardust Crusaders are along their journey.

Personally, there are some aspects to "Heaven" and the creation of what would later become to Stand "Made in Heaven" that remain unclear to me in how Dio came to these conclusions, but it does provide drive and information to Pucci himself during the later arcs of Part 6 and expands on some of the ideas somewhat, so there is purpose to how it is brought up here.

As I very much blew through the latter two-thirds of this book, it may have been my easiest read of the series yet and my favorite light novel so far.