The Last Hours Book 2: Chain of Iron Cassandra Clare

Cordelia Carstairs seems to have everything she ever wanted. She’s engaged to marry James Herondale, the boy she has loved since childhood. She has a new life in London with her best friend Lucie Herondale and James’s charming companions, the Merry Thieves. She is about to be reunited with her beloved father. And she bears the sword Cortana, a legendary hero’s blade.