** spoiler alert ** 
 I watched the Ghibli movie a while back but this book is so tiny I thought I could read it anyway. I think I almost like the story within the story device better than the Borrowers themselves, well, almost :p Although a bit sexist at times, it is also surprisingly mature about some things. Arriett's worldview is so very much her own than it is impossible to believe she was a fragment of the boy's imagination. Furthermore, we see Kate herself being created as a character on the very first page (and we know the whole book to be a piece of fiction), so who is real anyway? Really cool worldbuilding, might even read more of the series. 
 'Oh," said the boy again. He seemed to find it a safe sound, as lawyers do. "Are there many people like you?" 
 "No," said Arrietty. "None. We're all different." 
 "I mean as small as you?" 
 Arrietty laughed. "Oh, don't be silly!" she said. "Surely you don't think there are many people in the world your size?" 
 "There are more my size than yours," he retorted.