One factor could be the fan base's desire for romantic or intimate moments between the characters. Fans love to see their favorite characters in different scenarios, especially ones that involve some form of affection like a kiss. In the case of Issei and Ravel, it might also be about the potential for their relationship to develop in unique ways that the fanfiction writers can explore. For example, how their personalities interact during and after such a moment. Additionally, the fanfiction gives fans the opportunity to be part of the creative process, adding their own ideas and interpretations to the relationship.
The appeal might be in the unexpectedness. If in the original story their relationship is not that developed towards a kiss, seeing it in fanfiction can be exciting.
You can try looking on fanfiction websites like FanFiction.net or Archive of Our Own (AO3). Just search for 'Issei and Ravel' in the search bar on those sites and then filter through the results to find ones that might include a kiss scene.
One reason for the popularity could be the appeal of the characters Issei and Ravel themselves. Fans who love these characters might be interested in seeing their relationship take on a more romantic or even sensual turn in a lemon fanfic. Also, the lack of such explicit exploration in the official content might drive fans to seek it out in fan - made works. Additionally, the creativity of the fanfic authors in developing their relationship and the scenarios they create can contribute to its popularity.
Highschool DxD has a huge fan base, and Ravel is a popular side - character. Writers can take the existing lore and expand on it. For example, they can create new storylines for Ravel in different settings, such as in an alternate universe where she has different powers or goals. This gives a lot of creative freedom, which attracts both writers and readers.
The combination of Issei and Merlin is appealing. Issei is a well - known character with his own set of powers and personality, and Merlin is a very mysterious and powerful figure. When they are put together in a fanfiction, it creates an interesting dynamic.
I think Reddit can also be a good source. There are subreddits dedicated to the series that Issei and Ravel are from. You can post a request for Issei Kiss Ravel fanfiction there, and chances are some kind-hearted fans will point you in the right direction. Some users might even share their own unpublished works or recommend their favorite ones from other sites.
The Highschool DxD world has a unique blend of action, comedy, and fan - service elements. Fanfiction writers can build on this foundation, adding their own twists and ideas. For example, they can create new power - up scenarios for Issei or explore different romantic pairings, which attracts a lot of readers.
It's also about the potential for new storylines. Imagine Issei using Iron Man's suits in the middle of a battle in the DxD world. Or Iron Man having to deal with the supernatural elements of Issei's universe. These new combinations of plot elements are very appealing to readers. Additionally, the characters themselves are very popular in their respective fandoms, so when they are put together, it attracts fans from both sides.
One reason could be the unique take on the character Issei. In this fanfiction, it might explore his growth in a different way compared to the original source. It could give him more human - like qualities that make readers connect with him on a deeper level.
One reason is the chemistry between the two characters. Rias is a strong and alluring character, and Issei is a relatable protagonist. Their relationship has a lot of potential for different storylines, like how they grow closer and face challenges together.