I actually feel bad for Letty. Though this is being marketed as a romance-comedy anime, if you understand where Letty's aversion from the marriage is coming from, you'd want her to be freed too. She was way too young when she was made to take bridal lessons in preparation for marrying the prince, she was unable to enjoy her childhood and had always been restricted to follow a set rule/ettiquette plus as a young child the politics behind the engagement, the nobles' schemes and everything else is too overwhelming. Sure, the prince probably went through the same, but he was supposed to cause he was born into royalty. Letty could've atleast had a longer better childhood had it not been a royal engagement at such a young age, so I understand the resentment and aversion she had. I would've flipped too after years of suffering.