Themes like acceptance play a major role. The OC has to be accepted by Thorin and Company, and vice versa. There's also the theme of purpose. In the modern world, what is Thorin's purpose? What about the OC? They may find that their purposes are intertwined. And the theme of mystery is often present. There could be a mystery surrounding the dwarves' appearance in the modern world or something related to the OC's past that they all have to figure out together.
First, understand the characters of Thorin and Company well. Their traits from the original work can be translated into modern - day equivalents. For example, Thorin's leadership can be shown in a corporate setting. Then, develop the OC (Original Character). Give them unique qualities and a backstory that ties into the world of Thorin and Company. Maybe they're a new neighbor in their modern - day apartment complex. Finally, create interesting plotlines that involve both the known characters and the OC, like a mystery that they all have to solve together.
A common theme is adventure. Since Thorin is often on a quest in Middle - earth, the oc gets swept up in these adventures. For example, they might be traveling with him to reclaim Erebor. Another theme is love against the odds. Thorin is a dwarf king with many responsibilities, and the oc is an outsider, so their relationship faces many challenges.
One common theme is redemption. Often, the OC helps Thorin on his journey towards redemption, especially considering his greed in the original story. For example, in some fics, the OC might be the one to make Thorin see the error of his ways regarding the Arkenstone.
One common theme is adventure. Since Thorin is often on some sort of quest, the OC usually gets involved in these grand adventures. They might face orcs, dragons, or other perils together. Another theme is redemption. Thorin has his own flaws and sometimes the OC helps him in his journey of self - discovery and redemption.
Often, there is a theme of anticipation and future - building. Since the OC is pregnant, the fanfic may focus on what the future holds for their family. This could involve Thorin's thoughts on raising a child, his hopes for the heir, and how their relationship evolves as they prepare for parenthood. Additionally, the fanfic might touch on how the pregnancy affects the OC's role in the community or among Thorin's followers.
Adventure is a common theme. Since Thorin is often on a quest, the OC can be part of that journey. For instance, they could face orcs together, and this shared danger brings them closer.
One common theme is friendship. Just like in the original Oliver and Company, new OCs often form deep friendships with the existing characters. For example, an OC dog might become best friends with Oliver. Another theme is survival. Since many OCs are often strays or new to the city, they have to learn how to survive in the tough urban environment. And also, the theme of family. Sometimes an OC might find a new family among the characters of Oliver and Company.
One common theme could be the struggle with past traumas. Since Thorin has a complex backstory filled with loss, an OC (Original Character) might also experience nightmares related to similar events like the fall of Erebor. For example, they could dream of the dragon Smaug's attack, the destruction of their homeland, and the death of loved ones.
Another theme is redemption. Given his flaws and the mistakes he made in the original story, a lot of fanfictions focus on his path to redemption. They show him trying to make up for his past actions, whether it's towards his comrades or his own sense of honor.
Another theme is the reimagining of relationships. With Thorin being female, the relationships with the other dwarves, Bilbo, and even elves can change significantly. Her interactions with male characters might have a different dynamic, like a potential romantic angle with some characters that wasn't there before.