You can try searching on Archive of Our Own (AO3). It has a large collection of fanfictions across various fandoms, including for Rodrick and Greg. Just use the search function and type in their names along with 'yaoi' to narrow down the results.
Fanfiction.net could also be a good place. There are many fanfic writers who contribute to different pairings there. However, the tagging system might not be as refined as AO3, so you may need to do a bit more digging. Look for the relevant categories and search for their names within those.
There may also be themes related to personal growth. Through their relationship, both Rodrick and Greg could grow as individuals. Greg might become more confident, while Rodrick could become more understanding. These fanfictions can use their relationship as a catalyst for character development.
Another option is to ask on social media platforms. For example, on Twitter or Reddit, if you post a request for Greg and Rodrick fanfiction, there are likely fans who can point you in the right direction.
One popular Greg x Rodrick fanfiction might be 'The Unexpected Bond'. It explores their relationship in a new and interesting way, showing how they might grow closer over shared experiences like a crazy family road trip.
In the fanfiction, their relationship might start with Rodrick teasing Greg as usual. But then, an event like Greg getting into trouble at school and Rodrick being the only one who can help him out changes things. Rodrick realizes he has a responsibility towards his younger brother. This makes Greg see Rodrick in a new light, and they start to become closer.
There could be a fanfiction where Greg and Rodrick form a band together. Rodrick is the experienced drummer and Greg tries to learn an instrument to contribute. They face challenges like finding gigs and dealing with rival bands, which makes for an exciting story.
Well, there's a fanfiction called 'Greg's Hidden World' where the author explores the relationship between Rodrick and Greg in a more mysterious way. The story has a lot of twists and turns that keep you hooked. There's also 'The Lemon - Tinted Days' which is known for its vivid descriptions and how it portrays the two characters' interactions in a new light.
Some Tumblr blogs are dedicated to Diary of a Wimpy Kid fanfiction, including Greg x Rodrick. You can search for relevant tags on Tumblr and might discover some unique and interesting fan - created stories that you won't find on the bigger fanfiction platforms.
One of the best is MoonlightWriter. They have a knack for creating engaging stories that make you feel for the characters. And then there's RainbowPen, who is known for their creative take on the relationship between Rodrick and Greg in their fanfictions.
The relationship between Greg and Rodrick in Diary of a Wimpy Kid fanfiction is really interesting. Greg is the younger, more nerdy brother, while Rodrick is the cool, older brother. In fanfiction, some authors might depict Greg as being in awe of Rodrick's 'coolness' and Rodrick might start to see Greg as more than just a nuisance. For example, a fanfic could have a plot where Greg gets into trouble at school and Rodrick, instead of making fun of him, actually helps him out. This would be a big shift in their typical dynamic and could lead to a deeper, more brotherly bond in the fanfiction world.
Some other platforms like Wattpad might also have 'rodrick x greg fanfic'. However, the quality may vary. You'll need to look through the search results and read the descriptions and reviews to find the good ones.