It could be due to a miscommunication or a mistake in the magical or divine realm. For example, a messenger god might have delivered the wrong message, leading to Percy being forced to stay with Artemis. Or, in the chaos of a battle or a major event, Percy was caught in the crossfire of some sort of magical backlash that resulted in him being bound to Artemis's side. Also, there could be a plot device where the author wants to explore the relationship between a male hero (Percy) and a powerful female goddess (Artemis), so they create this forced - stay situation to drive the story forward.
Well, perhaps there's a power struggle in the mythological world. Some powerful being wants to control or manipulate Percy, and they see Artemis as a means to an end. By forcing Percy to stay with her, they can keep an eye on him or use Artemis's power and influence to their advantage. It could also be that Percy has unknowingly stumbled upon a secret or a power that is related to Artemis, and to protect it or study it further, he is made to stay with her.
One possible reason could be a misunderstanding. Maybe Percy accidentally disrupted one of Artemis's hunts or sacred rituals in the fanfic. Another reason might be that some prophecy or fate in the fanfic's made - up world has pitted them against each other. For example, if there's a prophecy that Percy's actions will somehow limit Artemis's power or freedom in the future.
Percy may initially resist with all his might. He's a strong - willed character. But as he realizes that fighting against it might not be the best option for the moment, he could start to observe Artemis more closely. He might learn from her, like how she handles her power and her connection to nature. However, there would always be an underlying sense of unease and a longing for his own world. He may also try to communicate with his friends secretly, hoping they can find a way to get him out of this situation.
Well, perhaps in this fanfiction, Artemis betrays Percy for Orion due to a prophecy. There could be a prophecy that states that Orion and Artemis together will bring about some great change or prevent a huge disaster, and Artemis believes she has to choose Orion over Percy to fulfill it. Also, Orion might have some sort of leverage over Artemis that forces her to turn her back on Percy.
One possible reason could be a misunderstanding. Maybe there was some miscommunication or false information spread that made Artemis think Percy had done something unforgivable. For example, if Percy was wrongly accused of harming one of Artemis' beloved creatures or desecrating her sacred places.
Well, one possibility could be that some powerful entity forces Percy into this marriage for political reasons. Maybe there's a power struggle in the mythological world and this union is seen as a way to bring stability. For example, Artemis might be against it initially because of her vow of maidenhood, but then she and Percy find a way to work together against the forced situation.
One reason could be as a form of punishment. Maybe Percy did something that Artemis considered disrespectful to the female gender or to her values as a goddess. Another reason might be for a mission. Artemis could think that in a female form, Percy would be able to infiltrate a place or situation that is only accessible to females.
One possible reason could be that Percy has shown great courage and a pure heart. Artemis might see in him the potential to be a great ally in the fight against the forces of chaos. Maybe Percy has also done something to earn her respect, like saving one of her hunters or standing up for what's right in a situation that involved her domain.
One possible reason could be differences in their divine natures. Percy is a son of Poseidon, a god associated with the sea and a more fluid, emotional element. Artemis is a virgin goddess of the hunt, very strict and unyielding in her ways. This contrast in their essences might lead to clashes and Percy's dislike.
A group of dark forces or minor gods could be the antagonists. They might believe that the union of Percy and Artemis would disrupt the balance in a way that benefits them. So, they engineer the situation where Percy is forced to marry Artemis, hoping to use the resulting chaos to their advantage. They would likely try to keep Percy and Artemis from finding a way out of the forced marriage.
One possible reason could be a misinterpretation of a prophecy. Maybe Artemis believes Percy is a threat to the natural order she protects based on a wrongly interpreted prophecy. For example, if a prophecy was worded ambiguously and she thought Percy would bring destruction to the wild, she might take drastic action.