One reason could be Percy's more fluid connection to his powers. Since he's been using his water - based powers for a long time, he's more in tune with them compared to Jason. So in a power - based showdown, Percy would have an upper hand.
Well, it might be that Percy has a more carefree attitude in some ways. He doesn't always follow the rules strictly and still manages to come out on top. Jason, who is more of a rule - follower and leader type, might envy Percy's ability to bend the rules and get away with it. Plus, Percy has a closer connection to Camp Half - Blood which has been his home for a long time, while Jason has to adjust to this new place and community, seeing Percy so well - integrated can make him jealous.
One reason could be Jason's popularity. Maybe Jason is getting more attention from their peers or the gods, which makes Percy jealous. Another might be related to a girl they both like. If the girl shows more interest in Jason, Percy could feel jealous.
Well, Percy has his water powers which are extremely versatile. He can control water in all forms, use it for defense and offense. For example, he can create huge waves to overpower enemies. Also, his connection to the sea is very deep and it gives him a constant source of power, which might make him stronger than Jason who mainly has wind and flight - related powers.
Maybe Jason is jealous because Jackson is more popular in the fanfiction world. He might get more attention, better storylines, or more fans. It could also be that Jackson has a certain charm or power in the fanfiction that Jason lacks.
In the fanfiction, it could be that Percy and Thalia have a long - established friendship. Jason, being new to their group or dynamic, might feel like he can't break into that bond. He may see how they rely on each other and communicate without words, and he wishes he could be part of that. The jealousy then stems from his desire to be as close to them as they are to each other.
One possible reason could be jealousy among other characters. Maybe there are those who envy Percy's powers and leadership, Jason's status as a hero, or Nico's unique abilities. Another reason might be a misunderstanding. For example, they could be wrongly accused of a crime they didn't commit, which leads to others turning against them.
One reason could be Percy's popularity. Percy has many friends and is well - liked in the demigod community. Jason might feel overshadowed by Percy's charisma and the attention he gets.
Well, it could be that in the fanfiction, Percy and Thalia are both really popular and well - liked among their peers. Jason, on the other hand, might feel overshadowed by them. He's jealous because they seem to get all the attention and admiration, while he feels like he has to struggle more to be noticed.
Well, they could start off on the wrong foot. Maybe Jason is a bit too by - the - book Roman and Percy is his carefree Greek self. But then they'd realize they have a lot in common, like their heroic natures. They might team up to fight a common enemy, using their unique powers. Jason with his lightning and leadership skills, and Percy with his water - based powers and street - smart thinking.
In the fanfiction, it could be that Jason has been through a lot with Percy. They might have shared many adventures and experiences that made Jason feel like he has a sort of claim over Percy. It could also be related to the world - building in the fanfiction. For example, if there are certain power dynamics or alliances that make Jason protective and possessive of Percy. Another aspect could be that the author wants to explore a complex relationship dynamic between the two characters, where Jason's possessiveness adds an interesting layer to the story.