The Mermaid Wars

An intelligent merfolk race lives beneath the Pacific Ocean. By tradition, when merfolk children turn eighteen, they leave home to train. They also seek out a creature they're destined to meet and raise it as a pet, using its intelligence to help themselves evolve.

The day the dreamer Qiqi turns eighteen, she sets out on her journey of cultivation, exploring the deep sea under the guidance of Kang, an obscure merfolk detective. As she pieces together her dreams and fragments of memory, Qiqi discovers that her past is full of strange mysteries. But before the truth of her origins can surface, a vast conspiracy is already closing in around her.