Sirens, Book 2, The Blue Planets World series

He's an alien. She's not quite human.

Can they survive an epic battle under the sea?

Sirens is the continuing story in an exciting science fiction series. When aliens beg refuge on Earth, they ask only for a home in the seas. But what if Earth's oceans aren't empty? The Phoke, the mer men and mermaids of Earth have remained hidden for centuries. But a Risonian water-borne illness forces them to come out of hiding and take a place at the negotiation table.