Friendship is another big theme. Writers often explore how the OC forms deep and meaningful friendships with Nami and Robin. They might start as strangers but gradually learn to trust and rely on each other. It could be through shared hardships or just by spending time together on the ship.
Adventure is a very common theme. Since Nami and Robin are part of the Straw Hat crew in One Piece, many fanfictions involve the OC joining them on their adventures in the Grand Line. For example, they might go on a quest for a lost treasure or to discover a new island.
The theme of growth is quite prevalent. The oc might start off as a weak or inexperienced character and through their interactions with Robin, grow in strength and knowledge. Romance is also a common theme. Writers often explore the relationship between the oc and Robin, from the initial attraction to a full - blown love story. Additionally, the theme of redemption can be found in some fanfics. Maybe the oc has a troubled past and Robin helps them find a new path in life.
Another theme is the exploration of Robin's past. The OC can be used as a tool to dig deeper into Robin's history as an archaeologist and her experiences growing up. They could go on quests to find more about her lost heritage or the secrets of the Poneglyphs. This adds more depth to Robin's character.
There's a fanfic called 'Fateful Encounters'. In this story, the OC meets Nami and Robin in a rather unexpected situation in a bustling port town. The author does a wonderful job of developing the relationships gradually. As the story progresses, they embark on a journey to find a hidden treasure, and throughout the adventure, the bond between the OC, Nami, and Robin deepens.
Maybe the OC is from a long - lost island with unique knowledge. Robin is interested in the historical aspects of this knowledge and Nami sees the potential for great treasures. The OC then has to deal with the different personalities of Robin and Nami. Robin is calm and intellectual, while Nami can be feisty. Their interactions lead to a series of adventures and a deepening of their relationships.
One common theme is the exploration of their relationship in different settings. For example, in some fanfictions, they might be in a situation where they have to rely on each other more than usual, which deepens their bond.
One common plot element is the oc having a special ability or knowledge that intrigues Robin. For example, the oc might be an expert in ancient languages, which catches Robin's attention as she has her own interest in history and archaeology.
One common theme is the power - dynamic. Naruto has his own set of powers and Robin has hers. Fanfictions might play with how these powers interact or complement each other. Another theme could be about cultural exchange, as Naruto's world and Robin's world in One Piece have different cultures.
Adventure is also a big theme. Since they are part of the Straw Hat Pirates, fanfictions often show them facing new challenges and exploring new islands together. Their relationship blossoms during these adventures as they rely on each other's strengths.
For the OC, give them a distinct personality trait. For example, if they are overly curious, it can lead to interesting interactions with Robin's love for knowledge and Nami's practicality. Show their growth over time, like learning from Robin's wisdom and Nami's street - smart ways.
One common theme is friendship development. Since they are both part of the Straw Hat crew, many fanfics explore how their friendship deepens over time. Another theme could be adventure - based, where they go on a special mission together and rely on each other's skills.