One common theme is redemption. Bucky often has a past he's trying to move on from, and Sarah can be a part of that journey towards a better self.
Family is also a theme. Sometimes, their relationship is explored in the context of building a new family or fitting into an existing one. Bucky might find a sense of belonging with Sarah and her family, which is a really heartwarming aspect in many of these fanfictions.
Another theme is love against all odds. Given their different backgrounds and the challenges in the fictional universes they exist in, their love has to overcome many obstacles. For example, Bucky's past as a soldier and Sarah's own personal struggles in her life.
One common theme is the exploration of their relationship against the backdrop of the complex Marvel universe. Since both characters have their own traumas and stories, fanfiction often delves into how they support each other through those.
Overcoming obstacles is another theme. They might face things like social stigma due to Bucky's past, or external forces trying to tear them apart. But they always find a way to stay together and fight through it all.
One common theme is loyalty. Their long - standing friendship and the lengths they would go to for each other are often explored. For example, in many fics, Bucky will always be there for Steve no matter what, and vice versa.
One common theme is redemption. Bucky has a complex past, and often in these fanfictions, the OC helps him find redemption or come to terms with his actions as the Winter Soldier. For example, in many stories, the OC shows Bucky that he is more than his past mistakes.
One common theme is redemption. Loki often has a past full of wrongdoings and in many fanfictions, his relationship with Bucky helps him on his path to redemption. Bucky, who also has a troubled past, can relate to Loki in some ways. Another theme is the idea of two outcasts coming together. Loki is an outcast in Asgard, and Bucky was an outcast among normal society after what Hydra did to him.
Adventure is another theme. They might go on a journey together, facing various obstacles. This could be in a magical realm or a post - apocalyptic world. Their skills and personalities are put to the test as they strive to reach their goals.
Friendship is a common theme. Given their characters, many fanfictions explore how they form a deep and meaningful friendship. They support each other through difficult times in the stories.
One common theme is the exploration of their complex relationship. Given their different backgrounds in the original stories, fanfiction often delves into how they bridge the gap between them. Another theme could be redemption, as both characters have had their share of difficult pasts.
One common theme is danger. Since Bucky is in the mafia, there's always a sense of peril around the reader character. For example, they might be targeted by rival gangs.
One common theme is loyalty. Steve and Bucky have a deep loyalty to each other that has withstood time and trauma. Another is redemption. Bucky's journey from being the Winter Soldier to finding himself again is often explored. Friendship is also a big theme, as their bond is one of the most important aspects of their relationship in these fics.