A storyline could involve Percy's child getting into trouble at school because of their unique abilities. Percy then has to step in and explain things to the teachers in a way that doesn't expose the whole demigod world. At the same time, he's trying to find a way to give his child a normal life while also preparing them for the inevitable battles they will face as a demigod.
Perhaps Percy is a single dad because his partner was lost in a battle against the Titans or some other great evil. In the fanfiction, he could be dealing with the grief of that loss while still being a great father. He might take his child on adventures around the places he used to go as a teen demigod, like the Labyrinth, but this time it's to teach his child about their heritage and how to survive in a world full of mythological threats.
One interesting storyline could be a single parent Percy Jackson trying to balance his demigod duties with raising his own demigod child. He'd have to deal with monsters while also making sure his kid gets to school on time. Another could be a single - parent character from the Percy Jackson world, like Sally Jackson, dealing with the loss of Percy in some alternate universe and how she copes with it. There could also be a story about a new single - parent demigod who shows up at Camp Half - Blood and has to adjust to the camp life while also taking care of their child.
One possible storyline could be Percy forming a band with his demigod friends. They could go on a tour across different mythical realms, performing for gods and monsters alike.
One possible storyline could be Percy leading a Titan rebellion against the Olympians. Since he has a connection to the Olympian side as well, it would create a very interesting internal conflict for him.
One possible storyline could be the OC being a new demigod who catches the attention of both Percy and Artemis. Maybe the OC has a special power that is crucial in a new threat that's emerging in the world of the gods. For example, the OC could have the power to control time briefly, which becomes important when an ancient enemy tries to rewrite history to gain power.
One possible storyline could be Percy losing hope after a major betrayal by a close friend in the demigod world. Maybe he feels like he can't trust anyone anymore and starts to isolate himself from his usual group. This could lead to a downward spiral where he even questions his own abilities and purpose.
One common theme is sacrifice. Percy often has to sacrifice his own time and freedom to take care of the child. Another theme is protection. He has to protect the child from the various threats in the demigod world. And there's also the theme of growth, both for Percy as he matures into a father figure and for the child as they grow up under Percy's care.
Sure. There's a fanfiction titled 'Percy Jackson: The Single Dad Adventure'. In it, Percy discovers a baby demigod and decides to raise it as his own. The story is filled with heartwarming moments as Percy tries to be both a father figure and a hero. He has to deal with the challenges of raising a child in a world full of danger. There are also some really cute interactions between Percy and the child as he tries to teach them about the world of the gods.
One possible storyline could be that they discover their sibling relationship while on a quest together and have to deal with the shock and how it changes their view of each other.
One possible storyline could be Percy trying to find a way to break the forced marriage. He might seek the help of the gods who are sympathetic to Artemis' situation. Another could be Artemis using her wits and powers to resist the marriage while Percy supports her from the sidelines. Maybe there's a prophecy involved that the marriage is a part of but they find a loophole.
One possible storyline could be that Percy sacrifices himself to save his friends and the entire demigod world from a powerful new threat, like an ancient primordial god awakened. His death could then lead to a new era where his friends are inspired by his selfless act and strive to keep the peace in his memory.