Illumi Zoldyck could also be a character in such fanfictions. Since Illumi has his own complex relationship with Hisoka, Hisoka's sister might get caught up in their interactions. And of course, there could be original characters created by the fanfiction authors, such as a mentor figure for Hisoka's sister who teaches her how to control her powers or a villain specifically targeting her because of her relation to Hisoka.
Hisoka's sister's friends or allies she makes along the way would also be common characters. They could be other up - and - coming Hunters or just ordinary people with special abilities. These characters help her in her adventures, whether it's in a fight or in solving a mystery. Another character that might appear is Ging, as he has a connection to the Hunter world and could potentially cross paths with Hisoka's sister in some way.
There could be original characters created specifically for the fanfiction. For example, a magical creature that befriends Natsu's little sister and helps her on her journey. But the core Fairy Tail characters usually play important roles as well. They are the ones who provide the familiar backdrop of the Fairy Tail world that the story is set in.
Temari and Kankuro, Gaara's siblings, are likely to be in the fanfiction as well. They could play protective roles towards their little sister, or they might have some conflicts with her as she tries to assert her own identity. And there could be some antagonists, like rogue ninjas from other villages who see Gaara's sister as a target for some reason.
Obviously, Gohan and his sister are common characters. Goku might also be there as their father. Vegeta could be included too, as he is often part of the Dragon Ball storylines. Maybe Piccolo as well, since he has a connection to Gohan.
One interesting plot could be Hisoka's sister getting involved in the Hunter Exam. She might use her unique skills, perhaps some that are similar to Hisoka's but with her own twist, to navigate through the challenges. For example, she could have a special ability to read opponents' intentions like Hisoka, but she uses it in a more empathetic way to avoid fights when possible.
There could be other minor characters from Forks that get more spotlight in these fanfictions. For instance, the classmates of Bella's little sister who start to notice that there's something strange about her. They might become curious and start to dig deeper into the secrets of the town, which then draws in the vampires and werewolves.
The Weasley family would probably play a role too. Ginny could be a role model for the little sister, especially in terms of being a strong female witch. Fred and George might teach her some of their pranks or tricks. And Mrs. Weasley could be like a second mother to her, showing her the warmth of a family. The Malfoys could also be in the story, perhaps as antagonists, creating conflict for the little sister and Harry.
Often, there are the victims or potential victims of Jeff. They might be ordinary people in the neighborhood who start to notice strange things going on and suspect Jeff. Another common character could be a detective or a police officer who is trying to solve the mystery of the killings and might eventually cross paths with the little sister.
Sakura can also be a popular character in these fanfictions. She might be a friend to Sasuke's sister, or there could be some sort of rivalry or cooperation between them. Also, characters from other ninja clans might be involved, like Shikamaru. His intelligence could be used to help Sasuke's sister in strategic situations in the story.
Well, often her father Chase Young himself is a major character. He might be guiding her or having some sort of conflict with her. Another common character could be Jack Spicer. He could be either an antagonist trying to use her for his own gain or an unlikely ally in certain situations.
The other Z - fighters like Gohan, Piccolo, and Krillin are also common. Gohan could be a friend and training partner to the reincarnated character. Piccolo might be a bit more reserved but still offer his wisdom, and Krillin could be the one who provides some comic relief in the story while also being a reliable ally in battles.