I happen to have an idea... One you may or may not like. My character, Leon, is a mercenary. Which means he carries out various tasks in exchange for money, mostly having to do with killing and/or hurting other people. However, he gets an offer from Flordia's parents, requesting her protection at all times in exchange for a sum of gold after anonymous threats detailing an upcoming assassination in the castle. What do you think? Leon hates royalty, so it would be interesting seeing how he interacts with the princess.
Or, maybe someone more kind, but with the same kind of story behind it. Instead of a mercenary only in it for the money, perhaps a quiet and mysterious vagabond like Tri, who's doing it simply out of the kindness of his own heart. Let me know what you think.