In this world, there is a well-known legend of an amazing warrior, known only as the Slayer. The Slayer is a single warrior, so skilled in the art of war, that he (or according to some legends, she) can destroy entire armies by themselves. It is said that, should the Slayer ever wish to, they could conquer the world… or end it.
In truth, however, there exists four Slayers, not just one. But the legends about their combat prowess is not far off.
In an era where great monsters roam the landscape, people hide behind the safety of small cities. Travelers are few and far between, and outsiders are generally distrusted. For centuries a secret cult called the Accusers have manipulated events from behind the scenes, whispering poisonous lies into the ears of isolated rulers. Turning nation against nation, and distracting the authorities with false alarms, all the while picking out the weaker city-states and targeting them for total destruction.
And what happens to a city that is targeted? Maybe a plague of werewolves will come and ravage the city. Or perhaps they'll incite a civil war. Or maybe, if the opportunity arises, the Accusers will turn their neighboring city-states against the target, causing it to be crushed under the weight of multiple enemies.
Oh, but things don't always go as planned. Sometimes there are… complications. Like the incident in Silus Village, a small town hidden beyond the treacherous Spider Canyon. When the Accusers moved in to take the city, a new Slayer calling himself Renjiro appeared, and slaughtered the Accusers who attacked his home. Despite his efforts, Silus was wiped out by undead plagues, and the man has set his sights on slaughtering the Accusers ever since.
And then there's Victoria Sarla, recently appointed queen of the Sarla Dynasty. She was trained by Renji to learn the ways of the Slayer, and now they work together. Renji and Vicky got married for political reasons, but that doesn't make their pairing any less of a threat. Vicky has her own beef with the Accusers, and she works together with Renji to root them out and execute them.
But even if the rank-and-file Accusers are sometimes incompetent, Matilda is still quite powerful. She's managed to turn the whole world against the two would-be heroes through lies and deciet. But then, Vicky and Renji answered this by simply going around and conquering everyone who came after them. If things get much further out of hand, Matilda will simply have to go and slay them both, personally.
But until then, if a few worthless minions die failing to assasinate the married Slayers, it really doesn't matter to the leaders of the Accusers. Matilda is still stronger than either of them, and she has the advantage of centuries of experience.