Annabeth could be the mother. Since she and Percy have a strong relationship in the original series, it's very likely that in a fanfiction they would have a child together. Their combined intelligence and Percy's powers would make for an interesting genetic combination for their child.
In Percy Jackson father fanfiction, the sea god Triton could be an antagonist. He might be jealous of Percy getting so much attention from Poseidon. The primordial sea gods or goddesses could also be antagonists. They might see Poseidon's relationship with a half - blood as a perversion of the natural order. And then there are always the minor gods who might feel that Percy and Poseidon are getting too much power and try to undermine them.
Well, sometimes in fanfiction, his brother might be a mortal who discovers his demigod heritage later. This could add an interesting twist to the story as he has to adapt to the world of gods and monsters. Or it could be a long - lost half - brother from a different camp, like a son of Poseidon from another part of the world who was hidden away for some reason.
Well, if Percy is the father of Zoe in fanfiction, it might mean that there are some hidden powers or abilities that Zoe could inherit from Percy. This could be a major plot point. Also, their relationship could be full of emotional turmoil. Percy, being the protective father, would have to deal with all the dangerous situations that Zoe gets into, just like he does with his other friends in the original stories.
Well, in this fanfiction, it could be that the author wanted to explore a different side of Percy's character. Being the 'Father of the Primordials' might mean he has the power to shape the very essence of the world in this fictional universe. It might also lead to some really interesting plot twists, like how he interacts with the existing gods and demigods, and how they react to his new - found status. It could also introduce new enemies or allies based on his role as the progenitor of the primordials.
One idea could be that Percy discovers he has a long - lost connection to Thalia. Maybe in a magical twist, a prophecy reveals that he is fated to be like a father figure to her. He could then use his powers and experience to train Thalia, much like Chiron trained him.
In a fanfiction, Percy could become Annabeth's father in a magical realm where the rules of family and time are distorted. Maybe a powerful god or goddess messes with their destinies. Percy would then have to navigate the new relationship while still dealing with his own heroic duties. He might struggle to balance protecting her as a father and respecting her as an independent demigod who is used to taking care of herself.
There could also be a situation where Naruto is like a father figure to the younger demigods. He could comfort them when they are homesick or feeling down. He would share stories from his own life in the ninja world, which could inspire the demigods to be brave and persevere in the dangerous world of Percy Jackson.
In a 'Percy Jackson Father of Chaos' fanfiction, Percy's relationships would be in upheaval. His friendship with Grover would face a test. Grover, who has always been Percy's loyal friend, would now have to deal with a Percy who is unpredictable at times. Percy might accidentally cause chaos that affects Grover's nature - related tasks. With the other demigods at Camp Half - Blood, Percy would become a sort of enigma. Some would look up to him as a new kind of hero, while others would be jealous of his new - found power. His relationship with the sea gods, like Poseidon, would also change. Poseidon might be proud that his son has such a powerful new role, but also worried about how Percy will use his powers and how it will reflect on the sea god's domain.
Their relationship would likely become even deeper. They would be partners not only in their heroic adventures but also in parenting. They would have to support each other in raising their child, like Annabeth helping Percy understand their child's academic needs while Percy might be better at teaching combat skills. They would also have to make decisions together about their child's future, whether it's about staying at Camp Half - Blood or trying to live a more normal life in the mortal world.