Decent book for some not-too-serious math and easy to read.
Roughly, the book is about the fundamentals of graph theory combining mathematical reasoning with computer science ideas. The main goal is to figure out algorithms to determine shortest routes in a graph. Hence, better-known algorithms, as well as ideas, are introduced, the book can be seen as a (very rough) introduction to graph theory.
It is not written as a typical textbook, instead, we are following the story of a 15-year-old girl Ruth who is taught graph theory by a super AI called Vim. That may be seen as a strength by also as a weakness of the book.
It certainly makes the book enjoyable to read and takes away the seriousness of a textbook.
On the other hand, the writing is in times ridiculous and it feels like the authors do not know how 15-year-old girls behave.
As both authors are from Munich, they have included several sights of Munich in most chapters to add some cultural variety.
In summary: This book is for you if you want a quick introduction to graph theory. If you do want a more concise one, though, you should pick up a textbook after this one.