A fanfiction could focus on their relationships. For example, how Sango and Miroku's relationship develops further with Kagome and Rin as witnesses. Maybe Kagome gives Sango some advice on dealing with Miroku's flirtatious nature, and Rin looks up to them as a couple, learning about love and relationships from them.
In a fanfiction, there could be a prophecy about four individuals who will bring balance to a certain region. Kagome, Sango, Rin and Miroku are thought to be those four. But there are also those who don't want the balance to be restored. So, they constantly face attacks and attempts to stop them. They travel from place to place, gathering allies and learning more about the prophecy. Miroku studies ancient texts for more details about the prophecy, Sango trains with local warriors to improve their combat skills, Rin helps with diplomatic relations among the different groups they meet, and Kagome uses her powers to protect them from magical attacks.
One great Kagome, Rin, Sango and Miruko fanfiction is 'The Adventure Together'. It focuses on their combined skills to face a new threat in a fictional world. The story does a great job of character development for each of them.
Another option is Wattpad. There are many fanfiction writers on there who might have come up with unique stories about Kagome, Rin, Sango and Miruko. You can also interact with the writers and other fans in the comments section.
There are some really interesting fanfictions involving Kagome, Sango and Lemon. You can start by looking on popular fanfiction websites like Archive of Our Own. Some might focus on their adventures together in the feudal era, exploring their relationships and how they interact with the strange elements in their world.
I'm not a huge fan of 'lemon' fanfics as they often focus too much on inappropriate content. However, if it's well - written in terms of character development for Kagome and Sango, it could be interesting. A good fanfic would explore their relationship deeper, perhaps how they support each other in their adventures. But usually, 'lemon' aspects can overshadow the real potential of the story.
One popular trope is the 'found family' where Kagome, Sango and Lemon form a very close bond that's like a family. Another is the 'power - up' trope where they gain new powers or abilities together. For example, they might discover a new spell that combines their individual strengths.
A good Kagome and Sango lemon fanfic should have a well - paced plot. It can't just jump into the 'lemon' parts right away. It needs to build up their relationship gradually. Maybe start with some small moments of connection, like how they share a secret or help each other out in a tough situation. Then, as the story progresses, the more romantic or sensual elements can be introduced in a natural way.
One common theme could be their friendship. Despite their different backgrounds, they support each other. Kagome is from the modern world and Sango is a demon slayer. Their bond can be a central theme, like how they rely on each other in tough situations.
Since 'lemon' fanfiction usually contains inappropriate content, I can't really recommend any. But in general, for Kagome and Sango, a fanfiction could be written about how they bond over their shared experiences in the Inuyasha world. They both have unique relationships with Inuyasha, and a fanfic could explore how they handle the challenges that come with those relationships while also strengthening their own friendship.