Forgive My Fins (Fins, #1)2010

Unrequited love is hard enough when you're a normal teenager, but when you're half-human, half-mermaid Lily Sanderson, there's no such thing as a simple crush. Especially when your crush is gorgeous (and 100% human) Brody Bennett. The problem is, mermaids aren't the casual dating type - the instant they kiss someone, they 'bond' with them for life. When Lily's attempt to win Brody's love leads to an enormous case of mistaken identity, she finds herself facing a tidal wave of relationship drama.