A simple way is to have the gods manipulate fate regarding Percy and Annabeth. For example, the gods could use their powers to set a fated path for Percy and Annabeth's relationship. Maybe the god of love is influenced by the other gods to create obstacles in their relationship as part of a greater fate for the demigod world.
One idea is to have a prophecy related to Percy, Annabeth and the gods which is all about fate. The prophecy could be so complex that it involves different gods' interests and the fated future of Percy and Annabeth. They have to navigate through this prophecy, understanding the motives of the gods and how it all ties into their own fated journey. They might even have to make sacrifices according to the fated prophecy, but they question whether it's really their fate or just the gods' manipulation.
One possible fanfic could be where Percy and Annabeth are faced with a fate that the gods have secretly planned for them. Maybe the gods, in their eternal scheming, decide that Percy and Annabeth's love is a threat to their power. So they create a series of challenges that seem to be fated for the couple. Percy and Annabeth, being the strong - willed demigods they are, fight against this pre - ordained fate. They might journey to different realms, trying to find a way to change their fate and prove that their love can withstand even the gods' meddling.
Fate in Percy - Annabeth fanfics can be a double - edged sword. It might be depicted as something that they are constantly fighting against. Maybe fate has destined one of them for a certain doom, but their love for each other and their own determination makes them strive to change that fate. In some stories, Percy might believe that he can defy fate to save Annabeth from a tragic end, and this belief drives the plot forward.
Aphrodite could also be one of the spying gods. Since she loves meddling in love affairs, and Percy and Annabeth's relationship is quite famous among the demigods. She might be spying to see how their relationship develops and perhaps add a little nudge here and there if she feels like it.
Another way is to have the New Gods bring in a new type of magic or technology to the Percy Jackson universe. This could change the dynamics of how demigods operate. For example, if the New Gods introduce a magic that can enhance a demigod's weapon but at a cost, Percy would have to decide whether to use it or not.
In this type of fanfic, the relationship might develop when Percy is put in a situation where he has to pretend to be Annabeth's boyfriend for some reason. As they play the part, Percy starts to notice little things about Annabeth, like the way she smiles when she's truly happy or how she gets excited about architecture. These small observations could start to chip away at his obliviousness and make him question his own feelings. Meanwhile, Annabeth hopes that this pretend relationship might turn into a real one, and as they go through different scenarios together, their relationship could grow from a one - sided love with Percy being oblivious to a mutual, deep - rooted love.
Percy might develop more of a steely determination. In Tartarus, he has to face extreme danger, which could make him even more resolute in protecting Annabeth and getting out. Annabeth, on the other hand, could become more resourceful. She'd have to use her wits in this strange and deadly place.
Another way is through the intervention of their friends. Their mutual friends could bring them together and encourage them to see things from the other's perspective. The friends can share stories about how each of them is really a good person deep down. This might soften their hearts towards each other.
The relationship could start with Percy and Annabeth being overprotective parents. Percy might be constantly worried about the baby's safety near water, while Annabeth would focus on teaching the baby knowledge and wisdom. As the baby grows, they could start to have little adventures together. For example, the baby could go on a mini - quest with them around Camp Half - Blood, which would strengthen their bond.
He could become withdrawn. Percy is a sensitive person at heart. So if Annabeth's actions are really hurtful, like if she cheats on him in a fanfic (although it's a very sad scenario), he would likely isolate himself from her and their friends. He might go off on his own to think things through and deal with his pain privately.
Annabeth might be initially in awe of Percy's new godly status. But she would quickly start thinking about how to use this new situation to their advantage. She is practical, so she would likely start planning how they can better protect their friends and the world.