In fanfiction, Sirius Black and Severus Snape often have complex relationships. Sometimes they are portrayed as rivals, with their past grudges from Hogwarts days still lingering. Their different loyalties, Sirius to James and the Order, and Snape to Dumbledore (while being a former Death Eater), add layers of tension.
I really like 'A Different Perspective'. In this fanfic, it's set post - war. Sirius, who survived the Battle of Hogwarts, and Severus, who has been pardoned, find themselves living in the same wizarding community. The story focuses on how they both have to deal with their past traumas and how they start to interact with each other. They start off avoiding each other but are gradually drawn together by their shared experiences and the realization that they are not so different after all.
I really like 'A Different Kind of Rivalry'. It shows a unique take on the relationship between Snape and Sirius. Instead of just focusing on their enmity from the original series, it creates a scenario where they have to work together and gradually start to understand and care for each other. It's a refreshing read.
They are an interesting pairing because they are such opposites. Snape is brooding and often seen as the outcast, while Sirius is more bold and carefree. In fanfiction, it's fascinating to see how these two very different personalities could come together.
One common theme is redemption. Given their rocky pasts full of enmity, many fanfictions explore how they can redeem themselves in each other's eyes. For example, Sirius might realize that Severus wasn't all bad, and Severus might come to terms with the fact that Sirius had his own reasons for his actions. Another theme is friendship against all odds. They are two very different characters, but fanfictions often show how they can form a bond despite their differences. This can be really inspiring as it shows that even the most unlikely pairs can find common ground.
The exploration of their shared past is also a big theme. Since they were at Hogwarts together, fanfictions often go back to their school days to show how their relationship could have been different. And there's the theme of the power of love and friendship in unexpected places. Despite their initial hatred, they find a connection that goes beyond what they thought possible. It shows that love and friendship can bloom even in the most unlikely situations.
There are also fanfictions where they are magically bonded in some way. This bond makes them feel each other's emotions and forces them to deal with their relationship on a much deeper level. They have to learn to tolerate and eventually accept each other, which leads to a very different kind of relationship compared to what we saw in the original Harry Potter books.
Love triangles are also somewhat common in Severus Snape and Sirius Black fanfiction. Sometimes it involves a love interest from the original series, like Lily Evans, and how their feelings for her, both past and present, impact their relationship with each other. It can add a whole new layer of drama and complexity to the story.
You can start by looking on popular fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfics about Severus Snape and Sirius Black. Just use the search function and type in their names. Another option is Fanfiction.net, though AO3 generally has more diverse and well - categorized works in my experience.
One popular piece of fanfiction in this category is 'Shadows of the Past'. It delves deep into the complex relationship between Snape and Sirius. The author does a great job of exploring their characters and how they might interact in a different, more intimate context. Another one is 'Unlikely Bonds' which shows their journey from animosity to something more.