Adventure is also a popular theme. They might go on a quest together, perhaps to find a lost magical artifact or to solve a mystery that has been plaguing Hogwarts for years. Their combined skills - Hermione's book - smarts and Lupin's practical experience - make them a great team for these adventures.
Another theme is the exploration of the werewolf aspect of Lupin. Fanfictions might show how Hermione reacts to Lupin's lycanthropy and how she might try to find ways to help him or understand it on a deeper level. For example, she could be researching ways to ease his transformations.
You can start by looking on fanfiction websites like Archive of Our Own (AO3). There are a large number of Harry Potter fanfictions there, and you're likely to find some that involve Hermione and Professor Lupin. Another option is Fanfiction.net. Just use their search function and type in relevant keywords like 'Hermione Lupin' to narrow down the results.
One possible plot could be Hermione seeking Lupin's help for some advanced magic study. Since Lupin is a knowledgeable wizard, he could guide her in a new area of magic, and during this process, a deep friendship or mentorship develops between them.
One common plotline could be Hermione seeking extra help from Professor Lupin in a difficult subject like Defense Against the Dark Arts. He might offer her special tutoring sessions, during which they develop a deep bond of mutual respect. Another could be them working together on a mysterious project related to the wizarding world's secrets.
One common theme is the exploration of female relationships outside of the traditional male - female romantic relationships in the Harry Potter world. It's about two strong female characters connecting on a deeper level.
One common theme could be the exploration of a forbidden relationship. Since Hermione is a student and Professor Lemon (assuming it's a made - up professor in the fanfiction world) is in a position of authority, the idea of crossing that line is often explored.
Power dynamics is another theme. Hermione as a professor has a certain amount of power and authority, and Malfoy, coming from a once - powerful pure - blood family, has to adjust to this new situation. Their interactions are shaped by these power dynamics, like in some fics where Hermione uses her power to put Malfoy in his place or to help him grow.
One popular 'Professor Lupin and Hermione fanfiction' is 'A Different Sort of Magic'. It explores an alternate universe where Hermione and Lupin have a unique bond that goes beyond the normal teacher - student relationship. They embark on a journey together to solve a mystery in Hogwarts.
There are many great authors in this niche. Some popular ones might include those who have a deep understanding of the Harry Potter universe. But it's hard to name just a few as there are so many talented writers out there.
One common theme is the exploration of an unlikely friendship or relationship. Given their different ages and backgrounds in the original series, seeing them interact in a new way in fanfiction is interesting. Another theme could be about growth. Hermione might grow in terms of her understanding of the more complex aspects of the wizarding world through Remus, and Remus could grow in terms of his ability to open up and trust again. Also, themes of protection and loyalty often come up, with Remus protecting Hermione from various threats and Hermione remaining loyal to Remus in difficult situations.