Dire Bound

In a country that has long fought immortal enemies across its border, warriors known as the Bonded form mental links with massive direwolves they ride into battle. Meryn Cooper, a commoner who resents the privileged Bonded, enlists in the army after her younger sister is kidnapped and taken across the front. To reach her, Meryn must endure the lethal Bonding Trials: four months of training at the castle, where she is paired with a feral direwolf that will not communicate, surrounded by rival trainees who despise her common blood, a harsh instructor, and a crown prince whose interest only makes her more of a target. Amid castle intrigue and hidden dangers, she faces a stark rule: bond or bleed.