A really interesting fanfiction concept could be that the tent of Thalia has some sort of connection to the underworld. The guardians are constantly on edge, trying to keep the dark forces from using that connection. Percy Jackson stumbles upon this situation and decides to help the guardians. They end up having to go on a quest to find an artifact that can sever the connection, all while protecting Thalia's tent. This would make for a really exciting and action - packed fanfiction.
There might be a fanfiction where they cry because they've failed in their duty as guardians briefly. In this story, perhaps they let a younger demigod get hurt and they cry in remorse. They then vow to be better guardians and train harder to prevent future failures.
In some fanfictions, Thalia's tent could hold secrets. It could be a place where ancient artifacts are stored that are relevant to the Percy Jackson world. Characters might stumble upon these secrets while seeking shelter in the tent. It could also be a place where new alliances are formed. Say, a character who was previously an enemy enters the tent and after some tense moments, decides to join forces with Percy and the gang.
There might be a fanfiction where Thalia is crying due to a prophecy she's learned about that seems to put her in a difficult position. The author could explore her internal struggle as she tries to figure out how to deal with it. She might be crying out of fear and frustration. Her relationship with other characters in the Percy Jackson world, like Annabeth, could also be explored in this context.
Well, a big theme is loyalty. The guardians are loyal to their duty of protecting the tent, and this loyalty can be tested in different ways in fanfiction. There's also the theme of discovery. Percy or other characters might discover new powers or secrets related to the tent or the guardians. For instance, they could find out that the guardians have a special ability that has been dormant for ages. And sometimes, there's a theme of friendship. Percy might form a friendship with the guardians while they are all working together to safeguard Thalia's tent.
There could be magical battles. Maybe some dark magic seeps into the tent, and the characters have to fight it off. For instance, a spell might be cast that turns the inside of the tent into a dangerous maze, and they have to find their way out while fighting off shadowy creatures.
A popular one is 'Thalia and Percy: The New Prophecy'. It takes place after the main series and imagines a new prophecy that involves both of them. The story has a lot of action and adventure, and the way the author writes their interactions is really engaging.
I really like 'Percy and Thalia's Adventure'. In this fanfic, they go on a quest together that was not part of the original books. The author does a wonderful job of capturing their personalities. Thalia's fierce and independent nature and Percy's loyalty are shown really well throughout the story.
In a fanfiction of Thalia's memories as a guardian, it could explore her relationship with other characters like Percy. Maybe she has memories of when Percy first arrived at the camp and she was initially wary of him. But as time passed, she saw his potential and they became comrades. These memories could shape how she continues to protect the camp and those in it.
Yes, there might be. You can check fanfiction websites like Archive of Our Own or FanFiction.net. Just search for 'Percy Jackson possess Thalia' on their search bars and you may find some interesting stories.
Yes, there are likely some out there. Fanfiction platforms like Archive of Our Own (AO3) or FanFiction.net probably have stories with this concept. However, it's important to note that this pairing is not part of the official Percy Jackson series canon.