Annabeth could be under some kind of magical influence. In the Percy Jackson universe, there are many magical elements. She could be cursed or charmed without her knowledge. This would be a very interesting take in a fanfiction as it would add an element of mystery and also give her a chance for redemption once the truth is discovered. Also, it could be that she has some internal insecurities that she hasn't dealt with and they manifest in this way, making her act out of character.
It could completely change the dynamic. Percy's trust would be shattered. His character might become more cynical or withdrawn. It could also lead to a new friendship or relationship as he tries to move on.
One possible outcome in this fanfiction could be Percy feeling a deep sense of betrayal. He might initially be in denial, not wanting to believe that he has been cheated on. This could lead to a downward spiral in his self - esteem as he questions what he did wrong in the relationship.
One reason could be that she's scared. The idea of becoming a mother at that point in her life might be overwhelming, and she might think she can't handle it with Percy. Maybe she wants to protect Percy from the difficulties that come with the pregnancy as well.
Well, Percy is a complex character. His reaction could depend on how much he knew about the pregnancy before Annabeth left. If it was a complete surprise, he might be in denial for a while. He could also start to blame himself, thinking he had somehow failed her. And then he might eventually turn that pain into a determination to be a better person, whether or not he ever sees Annabeth again.
Percy would likely feel a great sense of hurt and confusion. He might question his own judgment in trusting Annabeth. He could become more withdrawn and less trusting of others in general.
He might cope by throwing himself into his work or hobbies. For example, if Percy is into some kind of art or sport, he could focus all his energy on that. This would be a way for him to distract himself from the pain of being cheated on.
Perhaps Percy forgets an important promise he made to Annabeth. In their relationship, promises are significant. If he fails to keep one, like a promise to help her with a project or be at a certain place at a certain time, Annabeth would surely be mad. It could also be that Percy accidentally breaks one of Annabeth's creations or possessions, which she holds dear.
There might be some fanfictions out there that handle this topic in a more innocent or non - explicit way. However, it's important to note that in the official Percy Jackson series, such a situation doesn't occur. Some fanfiction authors may choose to explore this concept in a way that focuses on family, relationships, and growth without delving into inappropriate content. But it can be quite hard to find one that is completely family - friendly as this is a rather adult - themed idea to begin with.