Often, there are themes related to the Homestuck universe's overarching concepts. For example, the idea of fate and how their relationship fits into the grand scheme of things in the Homestuck story. Also, themes of friendship or something deeper evolving between them are quite common. Since Meulin is a rather curious character, her interactions with Kurloz can lead to themes of discovery, both of each other and of new aspects within the Homestuck world.
One common theme is the exploration of their different personalities. Meulin's bubbly nature against Kurloz's more reserved and perhaps menacing one. Another theme could be the idea of redemption or change, where one character helps the other to become a better version of themselves. For example, Meulin might inspire Kurloz to be more open and less harmful.
One place to start looking for 'Homestuck Meulin x Kurloz fanfic' could be Archive of Our Own (AO3). There are often a variety of fanfictions there that might suit your taste. Just use the search function and type in the relevant tags.
In fanfiction, the relationship between Meulin and Kurloz can be quite complex. Some fanfictions might depict them as having a rather strange or strained relationship. Given Kurloz's mute nature and Meulin's more outgoing personality, there could be interesting dynamics. For example, Meulin might try to draw Kurloz out of his shell, which could lead to both comical and touching moments.
I'm sorry I can't directly recommend specific 'Homestuck Kurloz x Mituna' rap fanfictions as there are so many out there and it's hard to keep track of all of them. You could try searching on popular fanfiction websites like Archive of Our Own (AO3) or Fanfiction.net. Just type in the relevant tags like 'Homestuck', 'Kurloz', 'Mituna' and 'rap' and see what comes up.
One interesting aspect could be the unique way the characters' personalities are expressed through rap. Kurloz is a rather complex character, and through rap, his motives and emotions could be explored in a new and exciting way. For Mituna, his own quirks can add a different flavor to the rap exchanges. Also, the fanfiction might play with the Homestuck lore in the context of rap battles or rap - related storylines, which can be really engaging for fans of the series.
I'd recommend checking out 'The Adventures of Nepeta and Equius' on Archive of Our Own. It has a great plot that really brings out the best in both characters.
One of the great things about Nepeta x Equius fanfics is the potential for character growth. We might see Equius becoming more in touch with his emotions through his interactions with Nepeta. And Nepeta could also learn about boundaries and self - control from Equius. Fanfic writers can take these two characters in many different and creative directions in their stories.
One great 'Homestuck Gamzee x Karkat' fanfic is 'The Bond Between Them'. It really delves into their complex relationship, showing how their different personalities interact. The author does a wonderful job of portraying Gamzee's laid - back yet somewhat unpredictable nature and Karkat's more uptight and easily - flustered self. It's full of heart - warming moments as well as some comical exchanges that are true to the Homestuck spirit.
The complex personalities of John and Rose make their relationship in fanfic interesting. John's easy - going nature and Rose's more intellectual and mysterious side create a great dynamic. Their interactions can range from comical to deeply emotional, which is fun to read about in fanfic.