One popular theme is the growth of their relationship. Starting from distrust or indifference and evolving into a deep friendship or something more. Another theme could be them facing challenges together, like a particularly difficult Titan attack where their combined skills are put to the test. Also, the theme of sacrifice might be present, where one is willing to sacrifice for the other in a life - or - death situation.
In Attack on Titan fanfiction, Armin and Levi often have an interesting relationship. Levi is the strong and stoic captain, while Armin is the intelligent strategist. Their interactions can range from mentor - mentee, where Levi imparts his combat and survival skills to Armin. Also, they might be comrades in arms, relying on each other during difficult battles. Their relationship can add more depth and complexity to the fan - created stories, exploring different aspects of their personalities as they face the challenges of the Titan - filled world together.
Some great Levi x Reader fanfics in the Attack on Titan universe often focus on their relationship development. For example, 'The Captain's Trust' which shows how the reader character gradually earns Levi's trust during their time in the Survey Corps. Another one is 'A Chance Encounter' that starts with a chance meeting between the two and how their relationship evolves from there.
One popular trope is the 'enemies to lovers' dynamic. Given their positions as former enemies in the main story, it's common for fanfictions to explore how they transition from hostility to love. Another trope is the 'hurt/comfort' where, for example, Annie might be injured or in distress, and Armin is there to comfort her, which deepens their bond.
One popular theme is their friendship evolution. As they grow up in the dangerous world of Attack on Titan, their bond changes and deepens. Another theme could be sacrifice. How far would Eren or Armin go to protect each other? And there's also the theme of trust. Given the complex and often deadly situations they face, trust between them is crucial and can be a major focus in fanfiction.
Well, in many fanfics, a popular plot is when Eren and Armin have a disagreement about how to deal with the Titan threat. Eren might want to be more aggressive, while Armin advocates for a more cautious approach. This leads to a rift between them for a while. But as the story progresses, they realize they need each other and come back together stronger. Another plot could be them exploring a new area outside the walls and encountering new types of Titans or mysteries that they have to solve together.
One interesting fanfiction could be where Mikasa and Armin go on a secret mission together outside the walls. They face many challenges and in the process, their relationship deepens as they rely on each other's strengths. Mikasa's combat skills and Armin's strategic mind work in harmony.
One common theme is loyalty. Armin and Erwin are both extremely loyal to their comrades and to each other. In fanfics, this loyalty often becomes a central aspect of their relationship. Another theme is leadership. They are both leaders in their own ways, and fanfics might explore how they lead together or support each other's leadership.
One common theme is redemption. Annie has done some pretty bad things in the series, and in many fanfics, Armin is a key figure in her journey towards redemption. Another theme is love in the face of chaos. Given the world they live in, filled with Titans and danger, their love is often portrayed as something that can survive and even thrive in such a harsh environment. Also, the theme of understanding each other's pasts is quite common. They both have complex backstories, and fanfics often explore how they come to understand and accept each other's past traumas.
Another theme is growth. They both grow as characters throughout the series, and in fanfictions, this growth is sometimes shown in relation to their relationship. Maybe Armin becomes more confident and Mikasa learns to open up more because of their bond.