Captive of the Snake King

A powerless bastard daughter of the Mage Emperor is sent in the place of her missing elder sister as a decoy bride for a neighboring king. They need his army to win a war against the invading kingdom to the south, but he'll only send aid for a queen.

The princess is taken the wrong way and winds up in the presence of a southern enemy soldier. After days in endless battle, the soldier wants nothing more than to return to his camp and return to winning the war, but the tempting princess is making the journey torturous.

Selene is promised to the gods, meant to become a priestess when her sister is found and rightfully married to the northern king. She questions everything she knows, including her feelings, when she learns who the enemy soldier really is. And by the time he learns that she's not the true born princess, and she's really the powerless daughter, it's too late for his heart as well.