[Note: This is in response to a question someone posted on Reddit. You can see the original post here. (opens in a new tab)]

Using that subplot properly, you can add a lot of richness to the worldbuilding, the story, and the Queen character.

Let’s start with one glaring problem: she has decided not to be with anyone except her love interest. But if she is a queen, she has the duty to produce a legitimate heir. You said that if she abdicated the throne, the kingdom would be thrown into chaos. The authorities, royals, and citizens of such an unstable kingdom would demand that the queen produce a legitimate heir to secure some form of political stability.

So the question is: if she will not be with anyone, how does she produce an heir? This question must be addressed, or it will distract your readers.

Luckily, addressing this concern is an opportunity to add richness, like I said before.

It’s rare for a monarch to rule in a vacuum. Even dictators have to consider what the townsfolk and people in the court think of their actions. Riots, assassinations, and coups are constant threats to any monarchy. On top of that, there are always threats from the outside, and the queen not having an heir would be a glaring sign of weakness to the kingdom’s enemies.

All of these threats and concerns can be used to enhance the story.

We can learn a lot about her and watch her grow as a leader and a person as she navigates these issues while staying true to her feelings for the one she loves. But how can she do this?

One option might be to choose a close family member as her heir. A lot of political and social problems could arise because of this, and watching her deal with the consequences of that choice, as well as how she makes that choice in the first place, could be great for the story.

There could be infighting amongst court members and people of Royal Blood as they try to get into her good graces to become the heir or get one of their family members to become the heir.

That’s just one option for that route. Opportunities there are limitless.

Or perhaps she decides not to choose an heir at all. Honestly, this would be a very stupid choice for the queen of an unstable kingdom. But if you want to put her in the worst-case scenario, this would be one option.

This would probably lead to assassination attempts or possibly even an overthrow of the government. People she thought were her friends turn against her. People she thought she could trust finally show their true colors.

Someone in the court who has gained the favor of the citizenry could make a good case that she is insane or does not care about the people and possibly get her thrown into prison.

Any of these scenarios could be used as a way for her to meet her love interest in person, and from there, it could go any number of fascinating directions.

These suggestions may not work with your main plot, but my main point is if she is not going to be with any other man, the problem of there not being an heir absolutely must be addressed in some way.