Well, it could be that Percy has witnessed some great injustice caused by the gods. Say, a friend of his was killed because of the gods' negligence. This makes him so angry that he decides to confront them and yell at them, not caring about the consequences. His yelling might be a way to show his defiance and also to make the gods realize the impact of their actions on the mortal world.
One possible plot could be that Percy has finally had enough of the gods' interference in his life and the lives of his friends. He might yell at them for their unfair treatment, like how they often use demigods as pawns in their games. Maybe he'll demand more respect for the sacrifices demigods make.
Well, it could be that Percy yells at Nico because he feels Nico is being too reckless in a dangerous mission. Maybe Nico is about to do something that could endanger the whole group, and Percy, being the protective type, loses his temper.
Percy is the central figure for sure. The gods, like Hades, might be there too if the story involves issues related to the Underworld. Grover could also play a role. He is Percy's friend and might be there to support Percy when he yells at the gods, or his experiences with the gods could be part of what drives Percy to yell. Chiron, the centaur, could also be a character as he is a mentor to Percy and could have some influence on the situation.
Well, it could be about Apollo's over - confidence. He might have boasted about his powers or achievements in a way that annoyed Artemis. In the context of the Percy Jackson universe, Artemis is very protective of her domain and those associated with her. If Apollo made a decision regarding something that was under Artemis' purview without consulting her, like interfering in the affairs of the hunters, Artemis would yell at him. Also, Apollo's past mistakes or actions that went against the values of the gods might be brought up by Artemis during her yelling.
In the fanfiction, Percy might sing to the gods as a way of expressing his own internal struggles. He could be feeling lost or confused, and the act of singing to the gods is his way of seeking guidance. He might pour out his heart about his identity as a demigod, his relationship with his father Poseidon, and his place in the world of the gods and mortals.
The plot might involve Percy having to complete a series of difficult tasks assigned by the gods. For example, he could be sent on a quest to retrieve a powerful artifact that has been lost or stolen.
Well, it could be about Percy having a new life in the realm of the gods. Maybe he gets special powers and training from them. He might also face new enemies that are threats to the gods, and he has to use his newfound abilities to protect the divine world.
Well, one possibility is that the gods are punishing Percy for some perceived disobedience. Maybe he defied their orders during a major quest and now they're making him suffer. For example, they could be sending him through never - ending trials in a hellish realm.
Perhaps the blessings make Percy a target. Other demigods or villains might be jealous of his new status. He then has to deal with the envy and threats while also trying to figure out how to fully utilize the blessings in a positive way. For instance, the gods' blessings might come with some sort of side - effect that he has to overcome as well.
Perhaps Percy leaves the gods after a great battle. He realizes that the cycle of the gods using demigods for their own purposes will never end. He decides to break free and start a new life. He could be seeking a place where he can be his own master and not be at the mercy of the gods' whims.
One possible plot could be that Sonic yells at Tails because Tails made a risky decision during a mission that almost put them both in danger. For example, Tails might have tried to take on a powerful enemy alone without waiting for Sonic's backup.