One possible theme could be friendship. Despite their different backgrounds and powers, they come together. Percy from Camp Half - Blood, Thalia as a daughter of Zeus, and Nico with his connection to the underworld. Their friendship could be tested and strengthened throughout the story.
Another theme might be self - discovery. Each of them has their own insecurities and hidden strengths. In the secret fanfiction, they could be on a journey where they not only face external threats but also have to look within themselves. For instance, Thalia might discover a new side of her power that she didn't know existed, while Nico could come to terms with his dual nature of being both a son of Hades and a friend to the living.
The theme of family could also play a big part. Percy has his own family issues, Thalia is related to the gods in a complex way, and Nico has his ties to the underworld family. The fanfiction could explore how they deal with their family legacies and how it affects their relationships with each other. Maybe they find a new kind of family in each other, different from their biological or divine families.
They could be like siblings. Percy and Thalia might act as the older siblings, protecting and guiding Nico. Percy, with his leadership skills, and Thalia, with her combat abilities, would be great at looking out for the younger Nico. They could also be like cousins, with a close - knit bond but still having their own individual family heritages that sometimes create interesting dynamics.
Perhaps it's a fanfiction focused on their relationships. They might form an unexpected bond in the story. Nico, who has often been a bit of an outcast, could find real friendship and acceptance from Percy and Thalia. They could start out on a simple quest, like finding a lost artifact, and during this journey, they learn more about each other and grow closer as friends.
One common theme is friendship. Their different personalities and backgrounds make for an interesting dynamic in terms of how they become friends and support each other. For example, Percy is often seen as the more easy - going and heroic type, while Nico has his dark and brooding side, and Thalia is strong - willed. Their friendship is often tested and strengthened in these stories.
Friendship is a very common theme. Since they are all from the same universe, their relationships are explored, like how they rely on each other in tough situations. For example, in many fanfictions, they help each other during battles against monsters.
One common theme is family bonding. Writers often explore how these three characters would form a family unit, despite their differences. Another theme could be the discovery of their shared heritage. Since they all have ties to the demigod world, there might be secrets about their family history that are uncovered in the fanfiction.
One challenge is the jealousy of other gods. Since they are new gods, the older, more established gods might not like the attention they get or the new ideas they bring. Another challenge is controlling their powers. As mentioned before, going from demigod to god means a huge jump in power level, and it's not easy to get used to. For example, Percy might accidentally flood a city while trying to create a small puddle for fun.
In fanfiction, Nico, Thalia, and Percy are often used to explore different storylines. They are well - known characters from certain fictional universes. Fanfiction writers might use them to create alternative adventures, develop relationships between the characters in new ways, or even put them in different settings than in the original works. For example, a fanfiction could explore a romantic relationship between two of them that was only hinted at in the original. It gives fans the creative freedom to expand on the existing lore and personalities of these beloved characters.
They could fight due to a prophecy. If there's a prophecy that involves one of them being the 'chosen one' and the others think they should be, it would create a lot of tension. For instance, if the prophecy says that only one of them can save the world from a certain doom. Percy, being the main character in many stories, might be assumed by the others to be the one, but Thalia and Nico may believe they have just as much right. Their struggle for that role could lead to a fight. And during the fight, they would use their unique abilities. Percy would call upon the water, Thalia would summon her lightning bolts, and Nico would raise the dead to fight on his behalf.
One possible plotline could be that Percy, Thalia and Nico are betrayed by their closest friends within the demigod community. Maybe they are framed for a crime they didn't commit, like stealing a powerful artifact. This could lead to them being hunted by their own kind. They would then have to go on the run, trying to clear their names while also facing various monsters that are after them because of the false accusations.
One interesting aspect of a Percy, Thalia and Nico bond fanfiction could be their adventures together. They could be on a quest to save the world from some new and powerful threat. Percy's leadership skills, Thalia's combat abilities, and Nico's connection to the underworld would make for a very dynamic trio.