One possible fanfiction could be about Lapis and Peridot fusing during a time of great danger on Earth. They fuse to protect their friends and the planet from a new, powerful enemy. Their combined powers create a unique and beautiful form that has abilities neither of them had alone.
One interesting story could be about Peridot and Lapis exploring a new planet together. They might encounter strange creatures and have to use their unique powers to survive. For example, Peridot's technical skills could help them build a shelter while Lapis uses her water powers to find a water source.
Another interesting one is 'The Tale of Lapis and Peridot'. In this story, they get involved in a mystery on Earth. The author does a great job of portraying their personalities and the way they interact with the human world.
There's 'The Adventures of Peridot and Lapis' which is quite popular. It follows their journey across different dimensions, facing various challenges. It has great character development for both of them.
The plot could involve Lapis and Peridot fusing accidentally at first. Maybe they are trying to work together on a project, like building a new structure for the Crystal Gems' base. Their powers interact in an unexpected way and they fuse. Then, they have to figure out how to function as this new being while also dealing with the reactions of the other Gems.
Maybe a time - travel plot where Steven, Peridot, Lapis, and Lemon are sent back to a crucial moment in Gem history. They have to work together to make sure the events unfold in a way that doesn't disrupt the present. Along the way, they learn more about each other's pasts and grow closer as a group.
One common theme might be the exploration of their relationship dynamics. Since they are two distinct characters, fanfic might focus on how they interact and get to know each other better. Another theme could be adventure, where they go on some sort of journey together.
You can try websites like Archive of Our Own (AO3). It has a large collection of fanfictions on various topics, including those related to Steven, Peridot, Lapis, and Lemon. Just use the search function on the site to look for relevant works.
Finding "peridot x lapis lemon fanfic" can be a bit tricky. Some fanfic communities on social media platforms might be a good place to start. You can ask fellow fans if they know of any good ones. Also, make sure to respect the rules and guidelines of each platform when looking for fanfic, especially if it involves certain pairings.