A theme that often shows up is Hisoka's relationships, especially his strange dynamic with Gon and Killua. Some fanfictions focus on how Hisoka views these young hunters and how his interactions with them shape the story. Also, his flamboyant and unpredictable nature is a theme that writers like to play with, creating all sorts of scenarios based on his unique personality.
The idea of Hisoka's past is also a common theme. Since the original series doesn't fully explore his backstory, fanfiction writers take the opportunity to create their own versions of his history. This could include his training, his early experiences in the world of hunters, and what made him into the character he is today. There are also fics that center around Hisoka's role in the larger power struggles within the 'Hunter x Hunter' universe, as he's always seeking power and influence in his own twisted way.
A prevalent theme is also the idea of an unlikely alliance. The OC might form an alliance with Hisoka for various reasons, like a common enemy or a shared goal. And of course, there's the theme of self - discovery. As the OC interacts with Hisoka and other characters from 'Hunter x Hunter', they often learn more about themselves and their own capabilities. For example, in some fanfictions, the OC discovers hidden powers while facing challenges related to Hisoka.
One common theme is the exploration of their opposing personalities. Hisoka is wild and unpredictable, while Machi is more reserved and practical. Fanfictions often play with how these differences can create either conflict or an unlikely attraction.
Another theme is the idea of an unorthodox relationship. They are both rather strange characters in their own ways, and fanfics usually show how their relationship is not like a normal friendship or romance. It's something much more complex and full of intrigue.
Another theme is the psychological aspect. Hisoka is a very complex character. Fanfics usually explore how the self - inserted character deals with Hisoka's unpredictable and often disturbing psyche. It can be about fear, fascination, or both.
Well, Hisoka's origin story in Hunter x Hunter is quite interesting. He hails from Meteor City, a place that's more like a dumping ground for the unwanted. Growing up there, he was exposed to all sorts of things that normal people wouldn't experience. His love for fighting strong opponents probably stems from the fact that in Meteor City, strength was the only way to get what you want. Hisoka's nen abilities are also a product of his environment. He's constantly evolving and seeking new challenges, which is likely a trait he developed while growing up in a place where only the fittest survive.
One popular Hisoka fanfiction might be those that explore his backstory. Since in the original 'Hunter x Hunter' his past is quite mysterious, fanfictions often fill in the gaps. For example, there could be stories about his early days as a Hunter and how he developed his unique nen abilities.
One great Hisoka - centered fanfiction might be those that explore his complex relationship with other characters in a more in - depth way. For example, a story could focus on his interactions with Gon and Killua from a more mature psychological perspective. It might show how Hisoka views their growth and potential as opponents or something more nuanced in his mind.
I really like 'Hisoka's Obsession'. It shows Hisoka's fixation on Gon in a more detailed and somewhat darker way. It adds layers to Hisoka's character while also developing Gon's reactions to Hisoka's strange behavior. The writing style is engaging and it's easy to get lost in this alternative take on their relationship.
The plot could also involve her having unique nen abilities different from Hisoka's. She might be on a journey to understand these powers and in the process, cross paths with the main characters from Hunter x Hunter. Perhaps she forms an unlikely alliance with Gon and Killua, who initially are wary of her because of her relation to Hisoka, but later come to respect her for her own qualities.
One common theme is her relationship with other members of the Phantom Troupe. Writers often explore how she interacts with Chrollo, for example. Another theme could be her abilities and how she uses them in different situations that the writer creates, which are not shown in the original anime or manga.