Perhaps in the fanfiction, there are other characters who are jealous of Annabeth's intelligence or skills. So they start spreading rumors or making unfair remarks. Percy defends her because he knows her true worth and capabilities. He would stand up and say things like 'You don't know her like I do. She's always been there for all of us.'
One possibility is that they've had a long and tiring adventure. After facing numerous challenges, they find a moment of peace and Annabeth, exhausted, falls asleep on Percy. It could also be a sign of their deep trust in each other. In fanfiction, this might be used to show the closeness of their relationship.
Well, it could also create a really deep connection between them. Since she can hear his thoughts, they might be able to communicate in a whole new way. They could team up more effectively in battles or quests. Annabeth could anticipate Percy's moves and decisions even before he makes them, making them a very powerful duo.
One possible scenario could be that Percy sacrifices himself to save Annabeth from a powerful and deadly monster. Maybe a huge and ancient sea creature that only Percy can hold off long enough for Annabeth to escape, but at the cost of his own life.
One scenario could be that Annabeth accidentally revealed Percy's secret identity to someone he didn't want to know. This could put him in danger and make him furious with her.
One possible scenario is that Annabeth might lie to Percy about something really important. For instance, she could lie about her whereabouts when she's actually meeting someone who is not a friend to Percy. When Percy discovers the truth, he would feel betrayed and hurt.
There might be some new characters introduced in the fanfiction who have different ideals or motives that clash with Annabeth's. These new characters could be the antagonists as they oppose Annabeth, and Percy has to step in. For example, if they think Annabeth's way of handling a certain quest is wrong and Percy believes in her, he'll fight against their ideas.
One possible scenario could be that they meet during a training session at Camp Half - Blood. Percy is new and a bit clueless, while Annabeth is already an experienced camper. She might be showing off her skills, and Percy is in awe of her. Then they start talking, and there's an immediate spark of mutual respect and a hint of rivalry too.
One possible scenario is when Annabeth goes off on her own to solve a mystery or complete a task. Percy would worry about her getting into trouble without his backup. Another is when there are new and powerful monsters around that specifically target Annabeth because of her reputation. He would be worried about her facing them alone.
Well, one scenario could be that Annabeth is reminiscing about their adventures together. In the fanfiction, she might be thinking about how Percy has saved her life multiple times. For example, during their battles against various monsters. Another could be that she's thinking about their relationship, like how they first met and how their feelings for each other have evolved over time. Maybe she's considering the future of their relationship in the context of the fanfiction world.
One possible scenario could be they sacrifice themselves to save their friends. Maybe they are facing an all - powerful enemy that can only be defeated if they give up their own lives. For example, if there is a dark force threatening to destroy their entire world and the only way to stop it is by using their combined powers in a self - destructive way.