Yes, the book is academic and it can sometimes bog down in boring rhetoric. It is rarely engaging to the point of one's being unable to put it down, but, after the longwinded introductory chapter, it does provide a very interesting overview of the history and significance of yokai in Japanese culture, past and present (including manga and anime). Michael Dylan Foster not only explains some of the chief representatives of traditional and contemporary yokai, he provides an excellent history of how yokai evolved as a serious subject of inquiry and also discusses the place of yokai in the matrix of Japanese culture. Academics are likely to appreciate the book for its insights more than those mainly interested in light reading about the yokai phenomenon. The book shouldn't be compared to those that are chiefly collections of old myths and legends.
For me, a major drawback is the relative lack of space devoted to one major form of yokai, the yurei or ghost, which is so important in Japanese literature, theatre, and art. And, despite the author's expert analysis of the kuchi-sake-onna or Slit-Mouthed-Woman, I was surprised that he never alludes to the possibility of potential influence from the gabu head in the bunraku puppet theatre. The gabu shows the face of a pretty girl but when the puppeteer pulls a string the upper and lower parts of the face are split by a gruesome, ear-to-ear mouth of sharp gold teeth, the effect of which is heightened by eyes that widen to become large squares, and horns that sprout from the hair. The character is really a serpent spirit in disguise. Come to think of it, Japan's upbiquitous serpents also get short shrift in this book, which, admittedly, does not attempt to be an encyclopedia, like Yokai Attack!
Pandemonium and Parade isn't perfect but it's a very worthy contribution.