Well, its popularity varies. In the niche community of Super Lovers fans, there is a significant group who enjoy reading and writing such fanfiction. They like to delve deeper into the characters' relationship and develop their own interpretations. But in a broader sense, compared to mainstream fiction, it's only popular within its specific fandom. It also depends on how much exposure and promotion these fanfictions get within the Super Lovers community.
One common non - adult theme is friendship. Their relationship could be explored in terms of a deep and loyal friendship, showing how they are there for each other through thick and thin.
Since 'lemon' fanfics are inappropriate, it's better to explore the positive aspects of the 'super lovers haru x ren' relationship in regular fanfics. You can look for ones that delve into their emotional bond, how they overcome difficulties in their relationship, or their growth as characters within the story.
You can try searching on some well - known fanfiction websites like Archive of Our Own (AO3). It has a large collection of various fanfictions, and there might be some related to Super Lovers Haru x Ren.
Swimming is also a big theme. Given that they are all swimmers, many stories will involve them training, competing, or having some kind of revelation related to their swimming careers. For instance, a story could be about how Rin's new training technique inspires Haru and Makoto to improve their own skills.
One great Rin x Haru mermaid fanfiction is 'Under the Sea's Embrace'. It beautifully weaves the mermaid lore with their relationship. The author creates a vivid underwater world where Rin, as a mermaid, discovers a connection with Haru that goes beyond the ordinary. It has some really touching moments that show their bond in a unique way.
I'm not sure specifically as there could be many different interpretations of a fanfic with 'makoto x haru'. It might be about a massage session between Makoto and Haru in a very relaxing and perhaps friendship - enhancing context. Maybe it details how the massage helps them unwind after a long day of training or just a tender moment between the two characters.
Overcoming obstacles together is also a frequent theme. They might face external threats or misunderstandings. In some fanfics, there are rival characters who try to come between them, but Tsuna and Haru always find a way to overcome these difficulties and strengthen their bond in the process.
One common theme is growth. They often start as two very different individuals, and through their interactions, they grow both personally and in their relationship. For example, Hibari might be more reserved and Haru more outgoing, and they learn from each other's traits.