The key elements in Sanji's back story are his family, the Vinsmokes. His different nature compared to his siblings is also important. And of course, his love for cooking.
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.
I think it might have been a character introduced to add depth to Sanji's backstory and motivations. But without more context, it's hard to say for sure.
Another characteristic is the exploration of new relationships. Since Sanji is a popular character, in female - centered fanfiction, new relationships with female characters can be created. These relationships can range from romantic to platonic, and they add new dimensions to Sanji's character. For instance, he might form a strong friendship with a female swordsman in a fanfic.
Sanji's back story is quite interesting. He grew up in the Vinsmoke family, which was a rather cruel and power - hungry family. Sanji was different from his siblings, he had a kind heart. His father was disappointed in him for his soft - heartedness and lack of the 'killer instinct'. Sanji was constantly bullied by his brothers. But he found solace in cooking. This led to his great passion for cooking later in life.
One common theme is his early culinary inspiration. It often shows how he got interested in cooking at a young age, maybe through observing his family or having a special moment with food.
Often, they involve a lot of emotional build - up. Since Zoro and Sanji have a complex relationship in the original story, in fanfiction, the kiss might be a result of resolving their differences or a sudden realization of deeper feelings.
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.