One plot idea could be that Percy, in his adventures, discovers a long - lost prophecy related to Athena. As he delves deeper into understanding it, he starts to develop a new - found respect and a kind of platonic love for Athena. He might see her not just as a goddess but as a key figure in the fate of the world and their relationship could be based on mutual understanding of the greater good.
Another plot could involve Percy getting a vision from Athena about a future threat to the demigod world. But the vision is so cryptic that he has to work closely with Athena to decipher it. Along the way, they build an unexpected bond, different from his usual relationships with other gods. Maybe Percy starts to see Athena not just as a powerful deity but as a mentor figure, and Athena starts to respect Percy's tenacity more than she expected.
One idea could be a new quest where Percy and Annabeth have to find a lost artifact related to Athena that was stolen by a rogue demigod. This would involve them traveling to new and dangerous places, facing off against mythical creatures they haven't encountered before.
Another plot could involve Percy having to prove himself to the children of Athena. Since he's not a child of Athena, they might be skeptical of his abilities at first. But as they face challenges together, like deciphering ancient prophecies that are hidden in Athena - related temples, Percy shows his worth through his quick thinking and battle skills. This could lead to a great friendship and mutual respect among them.
A really interesting plot could be that because he's Athena's brother, Percy is suddenly given access to some of Athena's knowledge. But this knowledge comes at a price. He starts to lose some of his own identity as a son of Poseidon. He has to go on a journey, both physically and mentally, to find a balance between his new - found connection to Athena and his loyalty to his father. Along the way, he meets various mythological creatures who either help or hinder him in this struggle for self - discovery.
One idea could be Percy struggling to fit in with Athena's children at first. Since he's used to being a son of Poseidon, he has different ways of thinking and acting. Another plot could involve him using his newfound Athena - given wisdom to solve a really complex mystery in the demigod world. Maybe he discovers a new prophecy related to Athena that only he can understand because of his unique position as her adopted son.
One idea could be that Percy has to seek Athena's wisdom to solve a complex mystery in the mortal world that is somehow related to the gods' ancient secrets. Maybe it involves a powerful artifact that was lost long ago and only Athena's knowledge can lead Percy to it.
One idea could be a story where Percy teams up with the Athena Hunters on a quest. Maybe they are searching for a lost artifact that has the power to change the balance between the gods. Percy's water powers could complement the skills and knowledge of the Athena Hunters.
Perhaps Athena's love for Percy causes a rift between her and her daughter Annabeth. This could lead to a complex story of family drama, loyalty, and love. Or, in some fanfictions, there could be a plot where Athena's love is a curse placed on her by an enemy, and Percy has to find a way to break the curse, all while they both struggle with their new - found emotions.
One idea could be Percy going on a quest to find a lost artifact of Athena that has the power to restore balance in the world of the gods. Another could be Percy having to face off against a powerful enemy who is specifically targeting him because of his relation to Athena. Maybe he discovers some long - lost siblings also sired by Athena during his adventures.
One interesting plot twist could be that Annabeth discovers a hidden power within herself that has nothing to do with Athena. Maybe she can suddenly communicate with mythical creatures in a way no one else can. Another could be Percy finding out that he has a long - lost sibling who is actually on the side of the enemy, but then later switches sides. And a third one might be that the Mark of Athena is actually a fake, created by an enemy to mislead the demigods and lead them into a trap.