One can finish reading this in a single sitting, and the book is so short that it doesn't even have page numbers.
That being said, it's a very useful reference for Japanese bathing etiquette, with not a single word wasted.
Also interesting to note is that the artist, Suehiro Maruo, a noted author within the eruguro genre, and has authored such things as Shoujo Tsubaki, an infamous work whose graphic violence and sexuality rivals that of De Sade's.