The theme of identity is also prevalent. Tom Riddle is on the cusp of becoming a dark wizard, and the oc's influence makes him question his identity. Is he doomed to be evil? Or can he be something else? These fanfictions often play around with this idea, and it makes for some really thought - provoking stories.
Redemption is a common theme. Since Tom Riddle later becomes Voldemort, many fanfictions with an oc adopting him focus on whether he can be redeemed through the love and care of the oc. Another theme is the power of family. The oc often tries to create a family - like environment for Tom, which is something he lacks in the original story.
One common theme is redemption. Since Tom Riddle later becomes Voldemort, the idea of fem Harry being able to change his path and redeem him is often explored. It gives a sense of hope that even the darkest of characters can be saved.
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.
Love in the face of darkness is a big theme. Despite Tom Riddle's evil tendencies, the oc wife falls in love with him, and the story explores how that love can survive. Also, secrecy is often a theme as Tom Riddle has many secrets that the oc wife slowly discovers throughout the story.
Another theme is the exploration of Tom Riddle's character. The OC serves as a tool to dig deeper into what makes Tom the way he is. Through his possessive actions towards the OC, we can see his insecurities, his thirst for power, and his disregard for others' feelings. Writers often use this as a way to expand on the already complex character of Tom Riddle in the context of fanfiction.
One common theme is redemption. Since Tom Riddle becomes Voldemort in the original story, these fics often explore the idea of whether he can be redeemed with Harry's help. Another theme is the power of family. Harry, having grown up without a proper family for a long time, tries to create a loving family for Tom. And the theme of changing destiny also runs through. It's about whether they can change the dark future that was set for Tom in the original story.
Power struggle is also quite prevalent. The OC often has some sort of power or knowledge that either challenges or complements Tom Riddle's own power. For example, the OC could be a seer, and their visions of the future clash with Riddle's plans. This creates a tense dynamic throughout the story.
The theme of mystery is quite common in these fanfics. Given Tom Riddle's mysterious nature, the oc often gets drawn into solving the mysteries around him. It could be about his past, his plans, or his real intentions. Additionally, the theme of friendship is also present in some 'tom riddle and oc fanfic'. The oc might try to befriend Tom Riddle, thinking they can change him through friendship, which leads to a series of events that show the complexity of such a relationship.
One common theme is the exploration of power. Since Tom Riddle is power - hungry, the male oc often gets involved in his pursuit of power in different ways, either as an ally, a rival, or someone trying to change him.
Love and redemption can also be a theme. Sometimes the OC's love for someone or something makes them try to redeem Tom Riddle from his dark path. This could be a romantic love for Riddle himself, or a love for the wizarding world that makes them want to change him. It adds a layer of complexity to the relationship between the OC and Riddle.
There's also 'Adopting the Dark Lord'. In this fanfiction, the oc is from a different magical family and takes Tom under their wing. The story delves deep into the Hogwarts era of Tom Riddle and how the oc's influence might change his future. It has some great character development and a lot of plot twists.