I really enjoyed this, it's a short novella but manages to pack a lot in. Cassandra has always fought against the restrictive gender norms of her society, becoming the first woman to study magic at the Great Library. But as the story starts, she's lost her ability to do magic, leaving her with an identity crisis and a broken engagement. When she stumbles across a troll and accidentally makes a deal with one of the elven lords, however, she's faced with a problem big enough to take her mind off her personal grief.