Every ten years, a 17-years old female is chosen to serve the Dragon, the sorcerer and liege of the area. Everyone believe that lovely Kasia will be picked, even her best friend Agnieszka. Instead Agnieszka is chosen. 
 Great writing, interesting and complex story with some misunderstandings, discoveries and growing up. And even a friendship can hide a darker side. I really like the relationship between Agnieszka and Kasia. Some real friendship and not a case of a token girl just here to make Agnieszka seems good. The two girls complement each other and make each other good. 
 It's a bit harsh for a YA book.