You live in a medieval world, where one's social standing is reflected by one's size. This world is governed by a multi-tiered serfdom, where the rulers of the larger, higher tiers effectively own the countries of the smaller, lower tiers. The rulers of said smaller countries often let themselves be owned by their larger counterparts for protection, but in other cases have their land taken in by force. Either way, a country taken in by a larger country's ruler must do all they can to endear themselves to their new master, lest their country be disowned and left to suffer in a world of giants, or be dealt a worse fate at the hands of those who tower above them.
The world at large is matriarchal, with women holding all the power, both in government, in business, and in the lower parts of society as well. The largest person of any tiered country is its Queen, Duchess, Countess, or whichever level of royalty said tier is at, with their closest female family members and servants at a comparable size, and their male relatives and servants kept much smaller. Only women can claim ownership of a lesser country.
The spectrum of sizes in this worlds runs the gamut from the lowest known peasants who are but specks in size, to the great empress of the world, who herself is the size of several galaxies. One can climb in society and grow in size by pleasing their superiors or gaining enough wealth, but may also be shrunk by offending those above them, breaking the law, or failing to pay taxes. And should you commit a grave enough offense, you'll find yourself a mere speck peasant...
You choose your gender and where you stand in society. Are you part of a middling female aristocracy, both flaunting your power over your inferiors and trying to appease those above you? One of their male servants, standing at ankle height to your ruler and praying not to offend her? A smaller, poorer woman who still owns a lesser nation and enjoys the small authority she holds over it? A peasant, serval or royal who seeks to climb in the world (and in size)? The supreme empress of the world, or one of her daughters? Or a pathetic speck peasant, trapped in a world several magnitudes larger than yourself?