Perhaps the fanfic would show Percy waking up excited for his birthday, but as the day goes on, not a single person mentions it. He tries to drop hints, but no one gets it. It could lead to him getting angry and having a bit of an outburst. Then, later, when his friends find out, they feel really guilty and plan an amazing party to show how much they care.
Well, the plot could be about Percy feeling really sad and left out when everyone forgets his birthday. Maybe he starts to question his friendships. He could go off on his own for a while, and then his friends realize their mistake and try to make it up to him with a big, surprise celebration.
Obviously, Percy would be the main character. His friends like Annabeth, Grover, and the others from his group would also be important characters. They are the ones who forget his birthday, so they play a big part in the story as they deal with the consequences of their forgetfulness.
There's a chance it could be Shikamaru. Despite his laid - back attitude, he is quite perceptive. He might notice Naruto's subdued mood and put two and two together, realizing it's his birthday. Then he could rally the others to quickly put together a belated celebration for Naruto.
Well, Naruto could initially be shocked that no one remembers. But then he might try to play it cool, because that's his nature. He could also think that they might be planning a surprise later. However, as time passes and still no one remembers, he would start to feel really down. He might even go off on his own to brood about it, wondering if he's not as important to his friends as he thought.
Well, it could start with Ginny waiting all day for Harry to remember. When he doesn't, she gets angry and ignores him. Harry, being a bit clueless, doesn't understand why she's so mad until Hermione smacks him on the head (figuratively) and tells him. Then he might plan a surprise party in the Room of Requirement with all of Ginny's favorite things, like butterbeer and Weasley sweaters in different colors.
It could also be that they are used to Stiles being the one who takes care of them and remembers things for them. He's always been the planner and the one to keep things in order. So they unconsciously assume that he doesn't really care about his own birthday as much as he does about helping them, and they forget all about it.
One way the plot could develop is that Naruto begins to trust the wrong people because he doesn't remember who he should trust. This could lead to him getting into dangerous situations. Meanwhile, his true friends are desperately searching for a way to reverse his memory loss. As the story progresses, Naruto might start to have flashes of his old memories, which would add some mystery and hope to the plot.
Well, obviously Merlin is one of the main characters since it's his birthday that's being forgotten. Arthur is often another main character. He might be one of those who forgets, or he could play a role in trying to make up for the forgetfulness later. Gwen could also be a main character, perhaps being too busy with her own tasks to remember Merlin's birthday.
It could. In many fanfictions where everyone forgets Merlin's birthday, it might end sadly as Merlin feels isolated and unloved. He might have expected at least one person to remember, and when no one does, it could lead to a melancholic conclusion with him feeling deeply disappointed and alone.
A cool plot could be that on Percy's birthday, the gods decide to grant him a special wish. But there's a catch - he has to complete a mini - quest first. So Percy, along with his closest friends, embarks on this quest that takes them to a mysterious island. On the island, they face various challenges, like fighting off strange monsters. When they finally succeed, Percy gets his wish, which could be something like ensuring the safety of all his friends at Camp Half - Blood forever.
One possible reason could be jealousy. Maybe Percy has some special abilities or achievements that make others envious. For example, his connection to the sea could be seen as a huge advantage that others might resent. Another reason could be misinformation. Someone might spread false rumors about Percy, leading others to believe he's done something wrong when he hasn't. It could also be that there's a misunderstanding about his relationship with Annabeth. Some might think he's getting special treatment from her or the other way around, which causes them to turn against him.