Well, in some fanfictions, it might start with Hermione noticing Snape's hidden acts of kindness. For example, she could observe him secretly helping students in ways that others don't see. This makes her question the common perception of him as a cold and mean teacher. As she delves deeper, perhaps she discovers his more complex past and motives, gradually building trust.
In some fanfictions, a great plot twist is that Snape is not really who he seems in terms of his magical abilities. He might be hiding a much greater power, and Hermione discovers this during a crucial moment. This discovery makes her trust in him even stronger as she realizes he has been hiding his true self not to intimidate others but to protect the wizarding world in his own way. Also, there could be a twist where Snape and Hermione are the only ones who can access a powerful, ancient magic, and this shared ability and the secrets it holds lead to a deeper level of trust between them.
In many such fanfictions, they are forced to work together on a task or to solve a mystery. This shared goal makes them interact more frequently. As they spend time together, Hermione begins to see Snape's intelligence and his complex personality. She realizes that there is more to him than the cold exterior he shows. Snape, on the other hand, starts to respect Hermione's intellect and determination. This mutual respect and understanding gradually build their relationship into one of trust.
One example could be 'The Unlikely Bond'. In this fanfiction, Hermione discovers Snape's hidden motives during the war and gradually comes to trust him. It shows how Hermione, with her inquisitive nature, digs deeper into Snape's actions and realizes he was not as bad as she initially thought. Another good one is 'Hermione's New Perspective'. Here, after a series of magical mishaps, Hermione and Snape are forced to work together. Through their interactions, Hermione begins to see Snape in a new light and trust is slowly built between them.
One reason could be that Hermione represents the type of student Snape doesn't really understand. He's used to students who are more slytherin - like, and Hermione's boldness and intelligence expressed in a very Gryffindor way might make him be hard on her. Additionally, in fanfiction, the writers might use this dynamic to create more tension and conflict in the story, which makes for more interesting plot development as Hermione tries to overcome Snape's difficult attitude towards her.
One reason could be that in fanfiction, authors often like to explore alternative character relationships. Hermione is highly intelligent and perceptive. She might come to trust Snape if she discovers his true motives behind his often - cold exterior. Maybe she stumbles upon his memories or some hidden evidence that shows he was acting in the greater good all along, like his role in protecting Harry from Voldemort.
You can try some popular fanfiction websites like Fanfiction.net or Archive of Our Own. Just type in 'Professor Snape Hermione Granger' in their search bars, and you'll get a list of relevant fanfictions.
The fact that they have such different personalities also adds to the allure. Snape is brooding and often seen as cold, while Hermione is intelligent, outspoken, and determined. When you put them together in a fanfiction, there are so many possibilities for character growth and relationship development. For example, they could learn from each other's strengths and weaknesses. Snape might learn to be more open from Hermione, and Hermione could gain more wisdom from Snape. There are also the underlying themes of redemption and unexpected friendships that can be explored in these stories.
One great fanfiction in this category could be 'The Unlikely Bond'. In it, Hermione stumbles upon Snape's hidden past during a library research project. It shows how she begins to see Snape in a different light, not just as the strict professor but as a complex person with a troubled history. It's really interesting to see how their interactions change as she gets to know more about him.
Yes, it is quite a popular trope in some corners of the Harry Potter fanfiction community. The idea of the usually stern and brooding Snape showing a different, flirtatious side towards Hermione creates an interesting dynamic as they are such different characters in the original series. It allows for exploring different character relationships and often involves bending the established personalities in creative ways.