One great Tom Riddle Jr and Hermione fanfiction is 'A Twist in Time'. In this story, Hermione somehow gets transported back in time and has to deal with a young Tom Riddle. It's really interesting to see how their different personalities clash and interact. The author does a great job of portraying Hermione's intelligence and Tom's growing darkness.
One common theme is the battle between good and evil. Hermione represents good with her values from the wizarding world, while Tom Riddle Jr is the embodiment of evil. Another theme is the power of knowledge. Hermione's vast knowledge often clashes or combines with Tom Riddle Jr's own understanding of magic.
One common theme is the struggle between good and evil. Since Tom Riddle Jr. is on his path to becoming Voldemort, the OC often has to decide whether to support his darkening ways or try to turn him towards the light. Another theme is the exploration of Tom's past. The OC may dig into his family history or his time at Hogwarts before he fully embraced the dark arts.
One popular 'tom riddle jr and hermione fanfic' is 'A Different Path'. It explores an alternate universe where Hermione somehow gets involved with Tom Riddle Jr in a rather complex relationship. Another is 'Time's Twist' which plays with time - travel elements to bring them together in an unexpected way.
Their relationship could start off with Hermione being extremely cautious around Tom Riddle Jr. But as she tries to understand him more, she might start to see his potential for good. Tom, on the other hand, could be initially intrigued by Hermione's intelligence and different way of using magic. As time passes, they could develop a mutual respect, with Hermione constantly challenging Tom's darker thoughts and Tom starting to question his own path because of her influence.
It's also about the time - travel or alternate universe concepts often used. For example, if Hermione goes back in time, she has the knowledge of the future. How will she use it to deal with Tom? Will she be able to change the course of history? All these possibilities make the fanfiction really engaging. And the power dynamic between them, with Hermione's magic being more learned but Tom's having a natural, dark power, adds another layer of complexity.
At first, it would probably be really tense. Tom is used to being on his own and having his own dark thoughts. Harry would be super cautious. But as time goes on, Harry's kindness might start to break through Tom's barriers. They could become like brothers, with Harry teaching Tom about the good in the world and Tom starting to trust Harry.
It could be a dark plotline. Tom Riddle Jr. is Voldemort, and having Hermione have a baby with him goes against so much of what is good in the wizarding world. It might involve themes of manipulation and a fall from grace for Hermione.
One plot idea could be that Hermione travels back in time and tries to prevent Tom Riddle Jr from becoming Voldemort. She might use her knowledge and magic skills to change his path. Another could be a scenario where they meet in an alternate universe where the rules of good and evil are more blurred, and they form an unlikely alliance to face a greater threat. Maybe Hermione gets trapped in a magically created world by Tom Riddle Jr, and she has to outwit him to escape and in the process, she discovers some hidden secrets about his past that could have changed his future.
A theme that is often explored is the exploration of the characters' pasts. Since Tom Riddle jr has a very troubled past, fanfictions might dig into it more deeply. And for Harry, his connection to Tom through the Horcruxes also plays a role. By exploring their pasts, the fanfictions try to show how they could have a different relationship than what was shown in the original books.