person a's family has a curse. every eldest born with a parent from their family is cursed with obedience, having to do what they're told no matter what. this curse leads to person a becoming the king and queen's advisor. person b is the child of the king and queen, and best friends with person a. person b is one of the only people in the castle that doesn't use person a's curse against them, and they spend a lot of time together.
