It often starts with curiosity. They meet in the Underground and are intrigued by each other. As they spend more time together, they start to trust one another. For example, Frisk might show Chara the power of kindness, and Chara might show Frisk some of the secrets of the Underground.
You can start by looking on fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfictions, and you can search specifically for ones involving Female Frisk and Female Chara. Another option is FanFiction.net, which also has a wide range of works. Just use their search functions and type in the relevant characters to find some interesting reads.
Some fanfictions focus on the relationship between Frisk and Chara in a more emotional way. For example, Chara might be haunted by their past actions, and Frisk tries to help them come to terms with it. It shows how their bond can be both complex and heart - warming, as they support each other through difficult times.
Often, there are themes related to self - discovery. Both Frisk and Chara have complex characters, and in fanfiction, they might explore their identities further in relation to each other. Also, themes of redemption can be present, especially considering Chara's somewhat controversial character in the original game. They might help each other to overcome past mistakes or traumas.
The main characters are Chara and Frisk. Chara is often a complex character with a troubled past in many interpretations. Frisk, on the other hand, is typically seen as the more positive and determined character who enters the Underground world.
A Core Frisk x Reaper Chara fanfiction could also explore different power dynamics. Core Frisk, with their strong will, might be able to influence Reaper Chara in positive ways. Reaper Chara, on the other hand, might have powers that they use to protect Core Frisk. Their relationship could be a balance of give - and - take. Additionally, the fanfiction could introduce other characters from the Undertale universe and show how they react to this unusual pairing. Some might be supportive, while others could be skeptical or even try to break them apart.
One common theme is friendship. Since Frisk and Chara are characters from the same game universe, their relationship development as friends is often explored. For example, how they support each other through various challenges in the Underground.
Another theme is self - discovery. As they interact, both Chara and Frisk might learn more about themselves. For example, Chara could discover a more positive side of themselves through Frisk's influence. In some fanfics, this is a central aspect of the story, with detailed descriptions of their inner thoughts and changes.
Good character development is key. The writer should show how Frisk and Chara deal with their pain and grow from it. Also, a believable backstory for their relationship is important.
Another way is to ask in undertale - related forums or communities. There are many fans who are into reading and writing fanfiction, and they can recommend some great stories. They might even have their own collections or bookmarks of good frisk and chara fanfictions that they can share with you.