You can start by looking on popular fanfic websites like FanFiction.net or Archive of Our Own. Just search for'minato x miya sekirei' and you'll likely find a variety of fics to choose from.
A minato x miya sekirei fanfic can take many forms. It might be a romantic exploration of their relationship, with tender moments and deep conversations. For example, the author could write about a time when Minato confesses his feelings to Miya and how she responds. Or it could be more action - oriented, with the two of them teaming up to fight against a common enemy in the Sekirei world. The fanfic might also introduce new elements to the Sekirei lore, like a new type of Sekirei that they have to deal with together.
One possibility could be a crossover universe where Naruto somehow ends up in the Sekirei world. The kiss between Naruto and Miya might be a result of a misunderstanding at first. Maybe Naruto mistakes Miya for someone from his own world and in a moment of confusion, there's a kiss. Then, it could lead to a whole adventure as they try to figure out how to get Naruto back to his own world while also dealing with the Sekirei rules and the reactions of other characters in the Sekirei world.
First, you need to establish the characters well. Since it's a crossover, make sure to describe how Naruto and Miya are in this new context. For the kiss scene, build up the tension before it. Maybe have them have a deep conversation where they realize they have a connection. Then, for the actual kiss, describe the emotions and sensations in detail. After that, introduce conflict. Maybe some of the other Sekirei are jealous or there are rules against their relationship. Keep the story flowing with action and more character development.
One great fanfic could be 'The Unseen Bond'. It delves deep into their relationship, showing how Minato's calm nature compliments Mitsuru's more reserved personality. The story might take them on an adventure within the world of Persona, facing challenges together and growing closer as a result.
A possible plot is that there's a new threat that combines the dark forces from Naruto, like the Akatsuki, and the antagonists in Sekirei. Naruto and Miya Sekirei have to put aside their differences and work together. Maybe they start by sharing their respective combat techniques. Naruto could teach the Sekirei about chakra control, while the Sekirei could show Naruto some of their unique powers that could be useful in combat against this new threat.
Perhaps the OC is a scientist who has been researching a new form of energy. This energy is actually what powers the Sekirei. The OC's research attracts the attention of a group of Sekirei. One Sekirei in particular befriends the OC to learn more about this energy. As they spend time together, the OC begins to understand the Sekirei's world better and helps them find a way to break free from the constraints of the Sekirei Plan.
One common theme is the growth of their relationship. Whether it's from strangers to friends or from friends to something more, the development of their bond is often explored. Another theme could be adventure. They might be on a journey together, facing various challenges that test their relationship. Also, self - discovery is a theme sometimes. As they interact with each other, they learn more about themselves.
Common themes could include friendship. Since they are two characters, their relationship might be explored in terms of how they support and understand each other as friends.
Another fanfic to consider is 'When Naruto Met Sekirei'. This one focuses on the initial encounter between Naruto and a Sekirei. It explores the confusion and curiosity that arises from their meeting. The author does a great job of portraying the different cultures of the two worlds and how Naruto and the Sekirei start to bridge the gap between them.
One possible aspect to analyze in a Kushina x Minato fanfic could be their relationship dynamics. Their love was strong and Minato was always very protective of Kushina. Fanfics might explore their courtship in more detail, like how they first fell for each other.