Serve and Protect the Princess of Nue
The refusal of affection for the Princess of Tulin is not a capital crime, but it has its consequences. Even though Lieutenant Ayan of the Imperial Palace Guard had not done anything like that.
It was only by great fortune that he would not end up in an unmarked grave under the Tulin walls, but in Nue, a small fortress in the middle of the Black Forest. If he does not want to return to his original destiny, he must become commander of the Princess Nue's personal guard.
Simple? Nothing a seasoned palace guard could do?