It could be that Aphrodite senses some unique potential in Percy when it comes to love. Maybe she foresees that he will play a crucial role in some grand love - related event in the future. So, to ensure that things go according to her plans, she becomes possessive. She doesn't want other forces or characters to sway Percy from the path she has in mind for him.
One example could be a story where Aphrodite constantly tries to manipulate Percy's love life to suit her own desires. She might interfere in his relationships with other characters, seeing him as a special project of sorts. For instance, she could prevent Percy from getting closer to Annabeth by creating misunderstandings, all because she wants Percy to be under her influence in matters of the heart.
In many fanfictions, Aphrodite's charmspeak can have various effects on Percy. It might be used to make him do things that he wouldn't normally do, like getting involved in some romantic scenarios he's not ready for. Sometimes, it could also be used to manipulate his emotions, causing him to have sudden and intense feelings for someone.
At first, it might be full of awkwardness. Percy, being used to a more down - to - earth kind of relationship, would be a bit overwhelmed by Aphrodite's grandeur. But Aphrodite, with her charm, would try to make Percy feel at ease. As time passes, they could start to understand each other better. Percy might teach Aphrodite about the value of loyalty and friendship from a demigod's perspective, while Aphrodite could show Percy the deeper aspects of love and beauty. Their relationship could grow into a more mutual and loving one, despite the initial differences.
In fanfiction, the concept of Ares being possessive of Percy can also stem from the idea of forbidden or complex relationships. The contrast between Percy's more heroic and noble nature and Ares' war - like and often brutish ways creates an interesting dynamic. Ares may view Percy as a symbol of what he can't be, and his possessiveness could be a way of trying to corrupt or change Percy to fit his own view of the world.
It could also be due to a sense of ownership. Percy has achieved a lot with the help of the gods, and Athena might feel that she has some claim over him because of the assistance she or other gods associated with her have provided. In the context of the fanfiction, this sense of ownership could translate into possessiveness.
Well, in some fanfictions, Hermes might be possessive of Percy because Percy could possess certain qualities or powers that Hermes wants to control or have an influence over. Maybe Percy has a unique connection to the world of the gods that Hermes sees as valuable.
Well, in some fanfictions, Luke might be possessive of Percy because he sees Percy as a symbol of power or potential. He may want to control Percy to use his abilities for his own goals, like in the original story where Luke has his own dark motives. Also, it could be out of envy. Percy has things that Luke might feel he lacks, so his possessiveness could be a way to try and take what Percy has for himself.
It could be because of the potential for a romantic relationship in fanfiction. Some fans like to explore the idea of Nico having romantic feelings for Percy. In that case, possessiveness might be a natural part of showing his intense emotions. He wants Percy all to himself, not sharing him with others, especially when there are other characters who might also be interested in Percy.
Piper McLean could be a great addition. Since she has some connection to Aphrodite already. She could either help Aphrodite in her plans or try to protect Percy from her. And of course, we could add some minor gods or goddesses like Eros. He could be Aphrodite's little helper in creating chaos with love arrows, which would definitely fit in with the lemon aspect of the fanfiction if it involves some love - related mischief.