The Days We Lost: Sanders Sides

Life: Virgil doesn't need it. He's sold off more days of his life than he can keep track of. He's realized that in Sandersia, you can get a lot of good things for just a few days, if you can find the right people. But when Virgil's father Emile falls victim to a nasty plague, Virgil must travel outside of the only kingdom he has ever known in order to find the cure.
And he is not allowed to go alone.

Life: Prince Roman of Sandersia feels he hasn't gotten enough of it. He longs for adventure and to find his soulmate, but his father, King Thomas, insists on keeping Roman and his twin brother Remus safely within the castle walls as much as he can. But when an unassuming peasant shows up to the castle for permission to leave the kingdom, Roman jumps on the chance to leave his royal life and discover what's beyond his father's reign.