Despite being a book for Japanese learners of English, Warau Eikaiwa can easily be used by Japanese learners for their own studies. The book is filled with funny and outright strange sentences that make reading entertaining. Plus, every single page comes with a comical drawing to help illustrate each sentence. Being that it is a book for native Japanese speakers, there are no romaji, furigana, or other helpful items typically used by beginner Japanese students. As a result, intermediate to advanced students may get the most out of this book. It doesn't explicitly teach grammar or vocabulary, but such things can be extracted from the sentences themselves if you are willing and have the time to do that. It should also be noted that there is some mature content in this book, which may actually be a selling point for some students.
While some of the English translations are strange and the formatting can get funky at times, the overall content is entertaining and provides a trove of uncommon words that you will only see at advanced levels. Check out the full review here.