Janavi. The Ember Town Series, #6

Janavi is a merperson and the ambassador between her people and the land walkers of Ember-a role she inherited upon claiming her true gender. When she takes custody of a human for Ember's council, she expects to have some fun at his expense. But an enemy pod tries to seize her family's home, and they are forced to fight for survival at all costs. Janavi is caught between the needs of her pod and navigating the politics of the land walkers.  Now Ember, the land itself, has started to awaken, and the human may be more important to Ember's future than anyone could have imagined.
Yet, victory will cost her pod more than they are prepared to lose. In Ember's river, survival is not just about strength. It is about knowing who you are and being willing to fight for it.