Another theme could be friendship. Before any romantic feelings develop, they could form a strong friendship. They might support each other in times of trouble, like when facing a common enemy. Their friendship could be based on mutual respect for each other's strengths. This friendship - first approach can then slowly transition into a deeper relationship as they spend more time together and get to know each other on a more personal level.
Romance is also a big theme. Writers often explore how they fall in love, maybe starting from initial misunderstandings and then gradually growing closer. Their different backgrounds can create interesting relationship dynamics. Since they come from different fictional settings, there could be cultural clashes and mutual learnings that contribute to their romantic development. This can involve things like Corrin teaching Robin about her world's customs and Robin sharing his knowledge of tactics and magic.
One common theme is adventure. Since both Male and Female Corrin are often involved in battles and quests in the game, fanfictions might continue their adventures together, facing new enemies and challenges.
One common theme could be the journey of male Corrin in the conquest. This might involve his growth as a leader and strategist.
Another theme is adventure. Since they are often from a game setting, they might go on quests together in the fanfictions. This can add an exciting element to the story as they face challenges side by side.
One common theme is friendship evolving into something more. Since they often interact in the game, in fanfiction, their bond can develop romantically. Another theme could be adventure. They might go on quests together, facing challenges side by side which deepens their relationship.
One common theme is adventure. They might go on quests together, facing various challenges. Another theme could be love and relationship development, showing how their feelings for each other grow over time.
One common theme could be emotional pain. Maybe Corrin is betrayed by someone close, like a friend or a family member, and has to deal with the heartache. Another theme might be physical harm in a battle or dangerous situation where Corrin is injured and has to struggle to recover.
One common theme is friendship. They might explore how female Corrin and Camilla become friends and support each other through various challenges in the Fire Emblem world.
Some fanfics might explore the idea of power dynamics. Given that Corrin may have certain powers in her original context, how she and the male reader interact in terms of power - like who protects whom, or how they combine their strengths - can be an interesting theme. There can also be a theme of self - discovery. As the male reader gets involved with Corrin, he may discover new aspects of himself, his abilities, or his place in the world of the story.
In Corrin x Scarlet fanfiction, a frequent theme is growth. Both characters grow as individuals and in their relationship. Another theme is the power of unity. They are stronger together and this is often explored. And the theme of destiny, as if their meeting and relationship is fated, is also quite common.