One common theme is loneliness. Chrollo often seems isolated in the original story, and fanfics tend to explore how his past experiences, like losing his family or being an outcast, led to this loneliness. Another theme is power - seeking. Fanfics show how his past traumas made him strive for power as a means of survival and control.
One great 'Chrollo Lucilfer backstory fanfic' is 'The Origins of Chrollo' on FanFiction.net. It delves deep into his early life, exploring how he came to form the Phantom Troupe. The author does a great job of showing his motivations and the events that shaped him into the character we know in the original series.
The theme of redemption can also be found. Sometimes, the fanfic will have Chrollo showing signs of wanting to change or make amends, especially in relation to Kurapika. And vice versa, Kurapika might start to question his single - minded pursuit of revenge in the face of Chrollo's complex character. Another common theme is the power dynamic between them. Given their different abilities and standings in the world of 'Hunter x Hunter', how they assert and negotiate power in their relationship is often explored in these fanfics.
Another theme is the exploration of their unspoken connection. They have a unique relationship in the original work, and in fanfiction, this is often expanded upon. It could be a connection based on mutual understanding of the harsh world they live in or their shared experiences in the Phantom Troupe. Some stories also play with the idea of a possible romantic undertone, although it's not always the main focus.
One great 'Hunter x Hunter Chrollo Fanfiction' is 'Chrollo's Redemption'. It explores an alternate path for Chrollo where he tries to atone for his past sins. The story has really good character development and the author does an amazing job of getting into Chrollo's psyche.
One idea could be a crossover with the world of Harry Potter. Chrollo could be a dark wizard from a far - off land who comes to Hogwarts to steal some powerful magical artifacts. He could use his Nen abilities in unique ways within the magical world, creating a really interesting dynamic as the students and teachers try to figure out his strange powers.
Sure. One popular 'kurapika x chrollo fanfic' is 'The Unlikely Bond'. It delves into a complex relationship between the two characters where they are forced to work together in a strange situation. Another is 'Fates Entwined' which focuses on how their different goals and personalities interact in an alternate universe setting.
You should also focus on character development. If you're crossing with the Fullmetal Alchemist world, consider how Chrollo would interact with the Elric brothers. He might see their search for the Philosopher's Stone as something he can use for his own purposes. Start with a small scene that sets the tone, like Chrollo arriving in Amestris and observing the alchemic practices there, and then build the story from that initial encounter.
He could be portrayed as a rival. Since Chrollo is such a powerful and complex character in Hunter x Hunter, his brother might be someone who challenges him in different ways, like competing for power or influence within the world of the story.
Chrollo's brother in fanfic can be a really interesting character. He might have similar powers or a completely different skill set. For example, he could be a master of a different type of nen ability that contrasts with Chrollo's. This could lead to some really cool plot lines where they either team up or are at odds with each other.