Phoenix (Dragon Eye Book 3)

Out of the ashes of a once-great dragon nation, a flame-colored dragon named Nia emerged. Alone for centuries, Nia is desperate to find more of her own kind. She indentures herself to the mad scientist Eudora in hopes of learning the whereabouts of her fellow dragons. But this information comes at a cost—if she flees, the mutant dragon-hunting yagi, trained on her scent, will hunt her down and destroy her.
When Felix, youngest son of the Melikovs, meets Nia, he’s smitten. Felix promises to help Nia in her quest to find more dragons, regardless of the danger.
But Ram, Felix’s brother, also falls in love with Nia. As they journey toward the mouth of a live volcano, death threatens—ahead, behind, and among them.

The Dragon Eye series books:
One: Dragon
Two: Hydra
Three: Phoenix
Four: Vixen
Five: Dracul
Six: Basilisk