Well, you can try searching on some popular fanfic platforms like Archive of Our Own. There might be a variety of 'chain sumeragi x leo fanfic' there. Just use the search function and type in the relevant tags.
One idea could be a story where Chain and Leo have to team up to solve a mystery in the hidden world of Hellsalem's Lot. They might start off not getting along well due to their different personalities, but as they face various challenges together, they gradually learn to trust and rely on each other.
Maybe Chain is revealed to be working for an organization that has ulterior motives regarding Leo. However, as the story progresses, she realizes she doesn't want to go through with their plans and instead decides to protect Leo at all costs. This would be a great way to show her character development and also create a lot of drama in the story.
One popular 'leo x raph fanfic' could be 'Bond of Brothers'. It delves deep into the relationship between Leo and Raph, showing their growth and how they support each other through various challenges. Another great one is 'The Unspoken Bond'. It focuses on their unspoken understanding and the times when they have to rely on that bond in tough situations. And 'Leo and Raph: A New Chapter' is also good, which explores their relationship in a different setting, like a post - apocalyptic world where they have to work together more closely than ever.
One common theme is the conflict between their two different natures. Shredder is often portrayed as the villain, and Leo as the hero. So, there's a push - pull dynamic of good vs. evil.
There's also 'Calypso's Choice: Leo'. This one is interesting because it focuses more on Calypso's perspective. It shows how she views Leo and their relationship. The descriptions of her feelings are very detailed, and it makes for a great read if you want to understand their relationship from her side.
The theme of mutual respect is often seen in 'leo x takumi fanfic'. They learn to respect each other's skills and qualities. For example, Leo might respect Takumi's precision in his actions, while Takumi respects Leo's intelligence. And there's also the theme of adventure, as they embark on various exciting journeys side by side.
Good 'leo x raph fanfic' often has well - developed characters. It should accurately portray Leo's leadership and calm nature as well as Raph's hot - headedness. The relationship between them should be complex, not just simple friendship or rivalry. For example, it might show how they understand each other on a deeper level despite their differences. Also, a good plot is essential. It could involve them facing a common enemy or dealing with internal issues within their group.
Another common theme is adventure. They often go on quests or adventures together. This could be something like exploring a mysterious forest or solving a mystery in their town. It adds an exciting element to the stories.