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.
One common theme is the power of their friendship. Since they are both passionate about swimming, their friendship is often shown as being strengthened by their shared love for the sport. For example, in many fanfictions, they train together and push each other to become better swimmers, which in turn deepens their bond.
A common theme is friendship. Since they are teammates in the swim club, many fanfictions explore how their friendship started and developed over time. It could be about how they first met and gradually became friends through their shared love for swimming.
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.
Love and friendship are common themes. Their relationship often starts as a friendship based on mutual respect for each other's musical talent, and then it slowly evolves into love. Another theme is self - discovery. Through their relationship, both Tokiya and Haruka learn more about themselves.
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. Their relationship might be explored in terms of how they support each other through different challenges.
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.
Friendship is a common theme. Nanami Haruka often forms deep friendships with different characters in these fics. Another theme is self - discovery. As he interacts with everyone, he learns more about himself.
One common theme is friendship turning into love. It often starts with the reader and Haruka being friends, and then their relationship gradually develops into something more romantic.
Often, the theme of self - discovery is present. As they interact, both Rin and Shiro learn more about themselves. Also, loyalty is a big theme. They show loyalty to each other in difficult situations, which is a central part of many rin x shiro fanfics. For instance, in some stories, they stand up for each other against powerful enemies.