The plot also matters. It could be a story that explores what would happen if the brothers rebelled against their father earlier. Or it could be a story set in an alternate universe where they have different abilities or goals. A good plot keeps the readers hooked. For instance, a plot where the brothers have to team up to save their mother from an unknown enemy would be really exciting.
One great Vinsmoke Brothers fanfiction is 'The Vinsmoke Legacy'. It delves deep into the backstories of the brothers, exploring their relationships with their father and each other in a really interesting way. It has some amazing character development that stays true to the original series.
Luffy would be furious. He'd immediately set out to rescue Sanji without a second thought. He'd probably charge straight at Doflamingo's stronghold without a proper plan at first, just driven by his anger and determination to get his crewmate back.
Well, Spy x Family fanfiction can be really interesting. Some fanfictions might explore different relationships between the characters in more depth. For example, they could focus on the bond between Anya and Loid in a new situation that wasn't shown in the original manga or anime. It's also fun to see how authors play with the spy and assassin themes in unique ways.
For Nami, her intelligence and cunning are key. She could use her smarts to get Sanji out of trouble in the fanfiction. Also, her love for money and treasure can add an interesting dynamic. For example, she might convince Sanji to go on a dangerous adventure in search of a valuable item, promising him new ingredients for his kitchen.
It can be developed through shared hobbies in the modern world. For instance, if they both like extreme sports, they could bond over skydiving or surfing. This would not only bring them closer but also show a different side of their characters.
Their relationship in the Zoro x Sanji Christmas fanfic could be presented through a series of challenges and reconciliations. For instance, when they are tasked with getting a Christmas tree for the ship. Zoro wants to just chop down the first tree he sees, but Sanji has very specific requirements. They argue, but then realize that by combining their ideas, they can get the perfect tree. This pattern of arguing and then coming together could be repeated throughout the Christmas celebration, showing the complexity and depth of their relationship.
Fanfics about Sanji can also be about his dreams and aspirations. In the original story, we know he has certain goals related to the All Blue. A fanfic could expand on this, perhaps he discovers a hidden route to the All Blue but has to overcome various obstacles, like dealing with a rival chef who also wants to claim the All Blue for himself, or facing a sea monster that guards the entrance to this mythical place.