Can the Grand Duke and the Marquis be Friends?

Obet has no idea what she signed up for when she attends the prince's oath ceremony disguised as her sick twin brother. Before she can make a good impression on the prince, a snooty young lord pokes fun at her, and the two of them spend the day bickering with each other. As it turns out, the lord is none other than Hinn, the son of the grand duke....