Well, in most cases, Luffy would use his unique abilities. He might use his Gum - Gum Pistol to knock out the bad guys. His superhuman strength and speed would allow him to reach Nami quickly and stop the assailants before any harm could be done. Luffy's sense of justice and loyalty to his crewmates are so strong that he would not let anything bad happen to Nami.
Luffy will most likely use his Gum - Gum abilities. He could stretch his arms to grab Nami and pull her away from the abuser quickly. For example, he might use Gum - Gum Pistol to knock out the bad guys who are abusing Nami.
One common theme is friendship. Luffy's act of saving Nami emphasizes the strong bond of friendship within the Straw Hat crew. It shows that they will always look out for one another no matter what.
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.
In some fanfiction concepts, Luffy could overhear a conversation. Maybe some of the villains are talking about their plans regarding Nami or boasting about how they've been treating her. Luffy, with his excellent hearing skills, picks up on this and figures out that Nami is in a bad situation.
Young Luffy in such a fanfiction would be extremely brave. He'd be the first to rush into danger without thinking twice about his own safety. His loyalty to Nami would be evident as he'd risk everything to save her.
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.
Love and attraction are very common themes. Sanji is often depicted as being head - over - heels for Nami, and his pursuit of her is a central part of many fics.
In nami and sanji fanfiction, the theme of admiration is quite common. Sanji admires Nami's beauty and intelligence, and Nami may come to admire Sanji's loyalty and cooking skills. Another theme is the idea of finding a home or a family. They are both part of the Straw Hat crew, and their relationship can be seen as a part of that family - like bond. Additionally, the theme of facing challenges together, whether it's pirates or other obstacles, and how this strengthens their relationship.
Yes, there might be some. You can try searching on popular fanfiction websites like Archive of Our Own or FanFiction.net. However, the availability can vary greatly depending on how active the 'One Piece' fanfiction community is in writing such stories.