In many such fanfictions, the relationship between Link and Saria is deepened by the challenges they face. Maybe Link returns to the forest at some point in his journey, and Saria has to use her powers and their connection to help him in a difficult situation, like fighting off a new threat to the forest.
One common theme is the idea of a childhood bond that develops into something more. Since they knew each other as kids in the Kokiri Forest, many fanfics explore how that innocent connection can transform over time.
I'm not sure specifically about 'link x saria lemon fanfic'. You can try searching on some popular fanfic platforms like Archive of Our Own. They usually have a wide variety of fanfictions, but make sure to abide by their terms and conditions.
Friendship is a common theme. Given their background in the Zelda series, their friendship is often explored in depth, like how they support each other.
There's a fanfic titled 'Link and Saria's Adventure'. In this, young link and saria go on a journey together. It's really interesting as it delves into their unique connection. They face challenges side by side and support each other, which makes for a great read.
Adventure is also a popular theme. Writers might create new quests or scenarios where Link and Saria embark on adventures together, facing challenges side by side.
You could start by looking on FanFiction.net. It has a large collection of fanfictions from various fandoms. Just search for the relevant tags related to 'link x saria'. But remember, not all fanfics are of the same quality, so you might need to sift through a bit.
The theme of growth is also present. As Link grows and changes through his adventures, his relationship with Saria can also change. Sometimes, he might have to make difficult choices that affect their bond, like choosing to save the world at the cost of not being able to return to the forest as often.
There's also 'Saria's Song Revisited' which is a great fanfic. In this one, the author uses Saria's song as a central theme. It shows how Link's memories of Saria and her song stay with him throughout his adventures, and how it might lead to a romantic connection between them. The writing is really engaging and the descriptions of the Hyrule setting are very vivid.
You can try fanfiction websites like Archive of Our Own (AO3). It has a vast collection of fanfics. Just use the search function and type in 'Link x Saria' and you'll get a list of relevant stories.