Warlord - Elizabeth Vaughan

Lara of Xy and her Warlord, Keir of the Cat, have been through much together. Lara left her homeland and her people for him, adopting his tribe as hers and learning their ways. Together they have overcome great trials, faced plague and insurgency, and found joy and happiness in each other's arms.
But now they face their most arduous trial: Keir must take Lara into the Heart of the Plains, where she will be tested and examined by the warrior-priests.
For Lara is the Warprize, but if the elders are to confirm her in her role, she must be accepted by a people who loathe everything she represents. And if she is found wanting, she will lose everything: her new home, her new people - and her Warlord . . .