The OC can be developed by having them learn from Vivi's strong sense of loyalty and duty to her kingdom. For example, if the OC was a bit of a carefree spirit before, seeing Vivi's dedication could make them more responsible. They could also develop their fighting skills by training with Vivi, who is no stranger to combat situations in the One Piece world.
Luffy would be the central figure. His relationship with Vivi is one of friendship and mutual respect. In the context of a harem, Luffy might not fully understand the concept at first. Vivi, on the other hand, could act as a mediator or an equal partner among the female characters in the harem. The harem members could all be united by their admiration for Luffy and his noble goals.
One way could be by focusing on their different personalities. Luffy's carefree and determined nature, Vivi's strong sense of loyalty and leadership. In the harem aspect, other female characters might be added. For example, Nami could be part of it due to her long - time relationship with Luffy. They could all go on adventures together, with Vivi guiding them in some aspects as she has knowledge of the Arabasta kingdom. The story could also explore how they all deal with the power of the One Piece world, with Luffy's goal of finding the One Piece at the center.
The popularity comes from the unique relationship between Luffy and Vivi in the original 'One Piece' series. Their friendship is very special, and fanfics allow fans to explore it further.
The OC could be a healer with a strange and rare form of medicine knowledge. In the fanfic, the crew gets injured during a big battle and the OC uses their skills to save everyone. Their medicine is based on a plant only found in Alabasta. Vivi then realizes that the OC's presence can be a great asset to the crew. The OC also has a dream to spread their medical knowledge across the world, so they join the crew on their journey. As they sail, they encounter different cultures and the OC learns new healing techniques, sharing their own in return.
There's also 'Luffy and Vivi: Reunion'. This fanfic focuses on what happens when Vivi reunites with the Straw Hat crew after a long time. It beautifully captures the emotions and the unbreakable friendship between Luffy and Vivi, with some really exciting action scenes in between.
One possible storyline could be that the OC is a wandering adventurer who saves Princess Vivi from a new threat in Alabasta. They then team up to discover the source of this threat which turns out to be an old enemy of the kingdom who has returned with a new power. As they journey together, they develop a deep friendship and respect for each other.
First, give the OC a strong motivation. For example, if they want to protect Alabasta like Vivi does, it gives them a clear goal. Second, a unique appearance helps. Maybe they have a distinctive hat or tattoo. Third, give them a special ability, like being able to control sand in Alabasta - style. These elements combined can make the character compelling.
Definitely not. 'One Piece' has a rich world of adventure, friendship, and self - discovery. Adding sexual elements through fanfiction is a distortion of what the original series represents. It also has the potential to make the fan community less inclusive and more uncomfortable for many fans who just want to enjoy the story in its intended spirit.
Well, you can write fanfiction that delves into the world - building of 'One Piece'. Maybe explore more about the different seas, the secrets of the Grand Line, or the history of the various pirate crews. You could also create crossovers with other non - sexual, family - friendly works, like how the 'One Piece' characters would interact with characters from a different adventure - based anime or manga in a friendly competition or joint adventure.