The change in their relationship depends on Sirius' reaction as well. If he's the type to not take it lying down, he might confront Hermione. But if he's more reserved, he could just keep his feelings to himself and let the relationship fizzle out. In either case, the relationship would no longer be the same as it was before Hermione's condescending behavior. It could also lead to a situation where other characters have to choose sides between them.
In such a fanfiction, this condescending behavior of Hermione towards Sirius can really turn their relationship upside down. Sirius is a proud character. If Hermione is condescending, he may initially react with anger. This could lead to arguments between them. As a result, their friendship or any alliance they had might be in jeopardy. They may avoid each other, and it could also affect how others in the fanfic view their relationship. For example, if they were both part of a group, the group dynamic could change because of the tension between them.
Well, it probably strains their relationship. Sirius might feel offended and start to distance himself from Hermione. He could be less likely to trust her or cooperate with her in whatever they were doing in the fanfic.
Often, it begins with Hermione trying to help Sirius deal with his post - Azkaban trauma. She uses her knowledge and compassion to reach out to him. As he heals, he starts to see her in a new light. Their relationship then grows as they start to understand each other better. The lemon parts usually are used to explore their more passionate and private moments, which are often written in a very tender and intense way, adding a new dimension to their relationship.
In these fanfictions, the soulbond often makes their relationship more intense. It creates an immediate connection that they can't ignore. For example, they might start to understand each other's feelings without words. It also deepens their loyalty to each other. They are more likely to protect one another at all costs because of the soulbond.
One reason could be that Hermione is under a lot of stress in the fanfic, and she takes it out on Sirius. Also, she might have some misinformation about Sirius that makes her think less of him. For example, if there are rumors going around about Sirius' past actions, Hermione might believe them without really getting to know him better. Another possibility is that Hermione is trying to assert her authority in a situation where she feels it's being challenged, and Sirius just happens to be in her way.
In fanfiction, when Snape and Hermione are in detention, their relationship could transform in several ways. Snape may be used to seeing Hermione as just another Gryffindor student who challenges his authority. But in detention, if she shows an aptitude for something he values, like a deep understanding of a particular potion or a magical theory. He could start to view her as an equal in some ways. Hermione, who has always seen Snape as a mean teacher, might find out that he has his own reasons for his behavior. Maybe he was bullied as a student too. This new knowledge could soften her view of him, and they could develop a relationship based on new - found respect and a bit of empathy.
At first, their relationship might start out as a simple acquaintance - type thing. Sirius sees Hermione as a smart young witch, but as he comforts her more, they start to develop a deeper bond. Maybe they start sharing secrets about their past traumas.
She becomes more confident. With Sirius' boldness and Remus' intelligence guiding her, she's more willing to take risks. For example, in some fanfictions, she might be more likely to stand up to bullies at Hogwarts.
The relationship could also take a more complex turn. Other characters might get involved in their conflict. Some might side with Sirius, thinking Harry was in the wrong, while others might try to mediate. This outside influence could either help or hinder the mending of their relationship, depending on how it's handled in the fanfic.
It could completely shatter their relationship at first. Hermione, being proud and intelligent, wouldn't tolerate such an insult easily. Their friendship might seem irreparable. However, if the story is about growth and redemption, Harry would have to go through a lot of self - reflection. He'd need to understand the depth of his wrong and work towards winning back Hermione's trust, perhaps by standing up against those with discriminatory views more actively in the story.
It could completely transform their relationship. Initially, they had a rather strained relationship due to Snape's often harsh demeanor and Hermione being a Gryffindor. But once he confides in her, she may feel a sense of responsibility towards him. This could lead to her defending him in certain situations. Snape might also open up more about his past and his reasons for his actions, which would make Hermione more empathetic towards him.
It deepens their connection. They become more in tune with each other's feelings. For instance, if Harry is sad, Sirius can sense it and vice versa. This makes their relationship more empathetic.