Elelín

Hundreds of years ago two warring species crash-landed on Earth. Unbeknownst to the humans, the Torak live among us. They're our friends... our neighbors. The Shantai hide away in the mythical city of Elelin. Neither of them forgot the war that destroyed their planet.
Airi has to make a choice. Will she kill to save thousands of lives? Will she destroy the Torak? It was her father's dying wish. But she meets Trey, the dark-haired human boy with dimples. And there's Calen, her sworn enemy. Soon she learns the line between friend and enemy becomes easily blurred.