so your family have generations upon generations of powerful strong female knights. (its basically in the genes) And you already have an obvious next monarch to your family, Leah. but somehow you still have to follow a stupid rule that breaks the nature of your family lineage. why would you purposefully weaken your noble family? thats like if in game of thrones (just an example, not what the show really is), for House Stark, instead of Robb Stark becoming the next head, with his leadership and achievement in battles, they choose Rickon Stark to be the next head because its a tradition that the youngest have to the next leader. see how stupid that sounds? this rule dont make sense when you have the different gender do the same shit you do without a problem. but somehow they need to get married for them to be an heir. if its to secure the next heir, then law should apply to the man also. neither man or woman can just pop out a child on their own. and dont tell me its trying to be realistic by mirroring our medieval times. its already unrealistic that you have consistent generations of stronger female knights in your family, stronger than your male ones even. its actually more unrealistic if you have a strong woman leader but not allowed to be one because of a stupid rule.
maybe i expect too much logic in a shojo manhwa.