Obviously, Anakin is a crucial character. The slaves themselves would also be important. There could be a young slave boy or girl who Anakin befriends and who serves as a symbol of hope for the others. And the slave masters, as the antagonists, are important too.
The plot might center around Anakin's moral struggle. On one hand, he has the Jedi teachings, but on the other, his own past as a slave. This internal conflict could add depth to the story as he decides how far he's willing to go to free the slaves. He may also have to deal with the consequences of his actions in the eyes of the Jedi Council.
Another way in fanfic could be that Anakin discovers a plot by the slavers that is against the greater good or some galactic law. By exposing this, he forces the system to free the slaves. He may also inspire the slaves themselves to rise up and demand their freedom, using his presence and the idea of Jedi - associated freedom as a catalyst.
The legal system in some fanfic settings might not recognize slavery as an illegal practice immediately. Anakin would have to fight through bureaucracy and convince lawmakers to change the laws. There could also be cultural acceptance of slavery in certain areas, and Anakin would have to overcome the deeply - rooted beliefs of the people there.
Well, in some fanfics, the story might start with Naruto getting a premonition or some kind of sign that Kurama is suffering under the seal. So, he decides to free Kurama. He then embarks on a journey to find a way to break the seal. Along the way, he meets various characters from the Naruto universe who either help or hinder his progress. Once he finally frees Kurama, they team up to face a greater threat to the ninja world that neither could have faced alone.
The main characters are Naruto and Kurama, of course. Naruto is the protagonist who wants to free Kurama. Kurama is the nine - tailed fox that is sealed within Naruto and is the one being freed.
I'm not entirely sure as 'percys slaves fanfic' could be about a very specific and perhaps fictional scenario within a particular fandom. It might involve characters named Percy and some sort of relationship with slaves in a fictional world created by the fanfic writer.
A 'Slaves of Harry Potter' fanfic could explore a really dark and alternative universe within the Harry Potter world. It might involve themes of power, oppression, and the fight for freedom. However, it's important to note that fanfics can vary greatly in quality and content.
Typically, you'll see a strong display of the friendship between Harry and Sirius. The fanfic might also introduce new challenges and obstacles that Harry has to overcome in order to free Sirius. It could be things like dealing with dark magic traps or facing powerful enemies. There might also be some exploration of the wizarding world's laws and how Harry bends or breaks them to achieve his goal.
There could be a hermit or an outcast Jedi or Sith on Dathomir. Anakin meeting this character could lead to a great revelation. Maybe this character has been in hiding on Dathomir for years, observing the balance of the Force there, and Anakin's arrival disrupts that balance and forces an interaction that changes Anakin's perspective on many things.