Well, often you'll see themes of growth. They grow both as individuals and in their relationship with each other. There can also be themes of support. For example, they support each other during tough training sessions or competitions. Sometimes, there are also themes of discovery, like discovering new things about themselves or each other through their interactions.
I'm not sure of a specific one off the top of my head. But you can try searching on fanfic websites like Archive of Our Own. They usually have a wide variety of fanfics including ones about Haruka and Rin.
One great place to find Rin and Haruka fanfiction is on Archive of Our Own (AO3). There are numerous well - written stories there. You can search by tags like 'Rin and Haruka' or specific relationship tags if you're looking for a particular type of story, such as friendship - centered or adventure - based ones.
A common theme could be friendship. Even in non - adult fanfiction, their bond as friends can be explored deeply. For example, how they encourage each other during tough times or how they share their dreams and fears.
One of the typical themes is the contrast between their personalities. Haruka is often seen as more cool and aloof while Usagi is bubbly. Fanfictions play with how these different personalities interact. Also, the theme of protecting each other is quite common, especially in stories where they face threats together.
One common theme is friendship development. Since they are friends in the original work, many fanfictions explore how their friendship deepens over time. For example, they might go through some challenges together that bring them closer.
One common theme is friendship. Often, the fanfics start with them as friends and then explore how that friendship might develop into something more. For example, they might face challenges together that strengthen their bond.
One common theme could be friendship exploration. Since gou and haruka are characters, fanfic writers might explore how their friendship develops. Another theme could be adventure, where they go on some exciting journey together.
Another theme could be self - discovery. Through their relationship, both Steven and Haruka learn more about themselves. Maybe Steven discovers a more assertive side of himself because of Haruka's influence, and Haruka might find a softer, more empathetic side of herself thanks to Steven. This mutual growth is often explored in these fanfictions.