One way could be through cowardice. If Percy is supposed to be a brave character in the original concept, but in the fanfiction, he runs away from a fight or danger that endangers the camp, he could be disgraced.
In fanfiction, often characters can have different storylines than the original. If Percy is from a particular series where there's a camp, perhaps he violated some important camp rules or values in the fan - made stories. This could be things like betraying a friend, failing at an important mission, or going against the moral code of the camp, thus resulting in his disgrace.
In some fanfictions, he might be exiled because of false accusations. Maybe someone frames him for a crime he didn't commit, like stealing a powerful artifact from the camp's vault. The camp leaders, believing the false evidence, have no choice but to exile him.
In this fanfiction, Percy might use his powers and leadership skills to bring order to the camp. Maybe he reorganizes the training schedules, making them more efficient for the demigods to improve their skills.
He could be angry. Percy has always been loyal to the camp, and being exiled unjustly would make him furious. He might vow to prove his innocence and show the camp they made a big mistake.
Perhaps they were caught in a compromising position while having a private moment. This could lead to all sorts of awkwardness among their friends at the camp. They might have to face some teasing or even get in a bit of trouble with the camp counselors for not following the rules.
The plot could involve Percy being abandoned by camp because the camp leaders fear his growing power. He wanders the world, feeling lost and angry. Percy then encounters a mysterious figure who offers him a way to get revenge on the camp. However, Percy, being a hero at heart, realizes that taking revenge won't solve anything. Instead, he decides to find evidence to clear his name and expose the real danger that the camp is ignoring while he was being pushed away.
In this fanfiction, Percy is likely a character who is considered the hottest guy at the camp. However, without more context from the specific fanfiction, it's hard to say more about him. He could be a new character created for this story, or a well - known character from an existing series that the fanfiction is based on.
Poseidon could arrive to warn Percy about an impending danger in the fanfic. He might bring along some underwater allies to help Percy and his friends at the Camp. It could be a really cool scene where Poseidon shows off his power, like creating a huge tidal wave just outside the Camp boundaries to make a point. And Percy would be both proud and a bit intimidated by his father's presence.
It could be one of the camp leaders who turned against Percy. Maybe they are jealous of Percy's popularity among the other demigods or they believe he is a threat to their power within the camp. So, they manipulate the situation to make it seem like Percy has done something wrong and get him abandoned.
Perhaps Percy was kicked out because of a prophecy that the camp elders misinterpreted. They thought that Percy's presence would bring great danger to the camp, so they made the hasty decision to expel him. It could also be that there was some sort of political intrigue within the camp. Some powerful figures at the camp might have seen Percy as a threat to their power and influence, and so they fabricated reasons to get him kicked out.