No, it is completely inappropriate. Such content involves vulgar and inappropriate sexual implications that go against the respectful and positive nature of fanfiction. Fanfiction should focus on exploring characters' relationships, adventures, and personalities in a more appropriate and family - friendly way.
One reason could be Snape's knowledge. Hermione, being a knowledge - seeker herself, might feel safe knowing that Snape has a vast understanding of magic, especially the darker aspects. So, she believes he can keep her safe from any threats related to that knowledge.
Well, it could be that the fanfiction author has created a unique backstory. For example, Snape could have saved Hermione's life at some point in the past, and she now has this deep - seated sense of security around him. Also, he might be a source of knowledge for her, and his presence, while initially intimidating, becomes reassuring as she realizes he won't let harm come to her in matters related to magic and the school.
One reason could be that he sees her intelligence and potential. Snape has always had a soft spot for those who are brilliant in potions and magic, and Hermione is top - notch in that regard. He might also recognize her determination and how she's often an outcast among her peers in a way, just like he was. So, he feels a sense of kinship and thus protectiveness towards her.
It's not appropriate. Fanfiction should be a way to expand on the world and characters in a way that stays true to their core. Hermione is often seen as a role model, especially for young readers. Incorporating such an inappropriate theme would go against the values that the character represents and the overall tone of the Harry Potter universe.
In some Hermione fanfiction, the concept of 'erection' might be used in a very discreet and tasteful way to show a character's physical reaction to Hermione's charm or intelligence. For example, it could be part of a scene where a male character is suddenly smitten by her in a more physical sense, but good fanfiction would handle it with subtlety.
I'm sorry, but this kind of content involves adult and inappropriate themes. J.K. Rowling's Harry Potter universe is a world that should be explored with respect and in a positive light, not with such vulgar ideas.
Often, it starts with a shared experience. For example, they might face a dangerous magical creature together. After that, Snape might show concern for Hermione's well - being, which begins to build her sense of safety around him.
Perhaps it's because Snape is a complex character in the original story. Fanfictions might explore his character in ways that make Hermione seem protected in those fictional scenarios. For example, some fanfictions could depict Snape using his knowledge and power to shield Hermione from various threats within the magical world they inhabit.
One reason could be the re - imagining of Snape's character. In fanfiction, he might be kinder and more understanding towards Hermione than in the original story. So, she feels safe in his presence.