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 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.
His friends at the camp would be worried. They might split up to search for him, which could put them in danger too. And this could lead to a rift in the group dynamics at the camp, with some blaming Percy for causing chaos.
In some fanfictions, Percy is heartbroken. He has considered the camp his home for so long, and being banished makes him feel lost and betrayed. He might go into a period of self - doubt, wondering if he really is as bad as they say.
One possible reason could be that he feels misunderstood. In the camp, everyone has high expectations of him as a son of Poseidon. If he makes a small mistake, it might be blown out of proportion. For example, if he accidentally causes a small flood during a training session, instead of being understood as still learning control over his powers, he could be harshly criticized. Another reason might be that he's tired of the constant danger at the camp. Every day there seems to be a new threat looming, whether it's a monster attack or some sort of internal camp conflict. He might just want to get away and have some peace for a while.
In some fanfictions, it could be that Percy has new, uncontrollable powers that the camp doesn't understand. They see him as a threat and banish him. For example, if he starts to show signs of a power that was once associated with an enemy of the camp. It's also possible that Percy's loyalty is questioned. If he befriends someone from an opposing group, the camp might think he has turned against them and banish him.
It could be due to a conflict with a particular authority figure at the camp. If he has a major disagreement with a camp leader over how to handle a situation, like dealing with a new enemy. Percy, being headstrong, might decide to run away and handle it his own way instead of following the camp's rules.
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.
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.