Soul of the Deep by Natasha Bowen

Simi prayed to the gods, once. Now she serves them as Mami Wata–a mermaid–collecting the souls of those who die at sea and blessing their journeys back home. But when a living boy is thrown overboard, Simi goes against an ancient decree and does the unthinkable–she saves his life. And punishment awaits those who dare to defy the gods. To protect the other Mami Wata, Simi must journey to the Supreme Creator to make amends. But all is not as it seems. There’s the boy she rescued, who knows more than he should. And something is shadowing Simi, something that would rather see her fail. Danger lurks at every… Read more.