Iron Flame by Rebecca Yarros

 

It's the second year of training for those who wish to serve as dragonriders for the government.  Violet was expected to die in the first year along with those others who were too weak to make it through training.  But her iron will took her through that and brought her a love in Xaden Riorson that she never expected.  

But now Violet's eyes have been opened.  She is learning more and more about the secrets of the kingdom and the lies that everyone has been told.  She knows that both her sister and brother are alive and serving, her sister as a dragonrider, her brother with the opposition.

Violet has made new enemies including the head of training for the core and he delights in doing anything he can to push her past her limits, hoping to kill her.  But the woman who bonded with the biggest dragon alive isn't the kind to be killed and she fights back with everything she has.  Can she and her friends win?

This is the second novel in the Empyrean Empire series.  There is lots of steamy sex and the plot moves quickly.  Violet and Xaden have a bond that can't be broken and Violet and her cadre are loyal to each other to the death.  There are twists and turns and more secrets of the Empire are revealed.  This book is recommended for fantasy readers.