One common theme is the discovery of the magical world. The Muggle OC usually starts off not knowing about magic and then has this amazing journey of discovery. Another theme is the clash of cultures, between the Muggle world and the wizarding world.
The theme of friendship often plays a big role. The Muggle OC forms deep friendships with the characters from the Harry Potter universe. For example, they might become really good friends with Harry or Hermione. Also, the idea of acceptance is common. The Muggle OC has to be accepted by the wizarding community, and they also have to accept this new world that's so different from their own. There can be a lot of drama and character growth around this theme.
One common theme is self - discovery. The OC often has to figure out their place in the wizarding world. Another is friendship, as they make new friends like the main characters in Harry Potter. For example, they might become friends with Harry, Hermione, or Ron.
Another theme is the role of magic in a Muggle - style war. Some fanfictions explore how magic can be used as a weapon, a tool for espionage or a means of protection. For instance, a wizard might use magic to disrupt Muggle military operations or to protect Muggle civilians from harm. It's about how magic can change the dynamics of a war.
One common theme is the discovery of the wizarding world. Muggle families often find out about magic in these stories, like in 'The Granger Family Secrets' where Hermione's family discovers more about the magical world she's a part of. Another theme is acceptance. The muggles have to accept the existence of magic and sometimes their own family members' magical abilities, as seen in 'A Muggle - Born's Family Tree'.
Friendship is also a big theme. These OCs usually form bonds with Harry Potter and his friends. Their friendships are often tested by the OC's family background. For instance, Harry and his friends might be initially suspicious of the Black OC because of the family's reputation, but as they get to know the OC better, they realize they are more than just their family name and form strong friendships. This theme of overcoming prejudice through friendship is quite common in such fanfictions.
One common theme is self - discovery. The oc often discovers new things about themselves while interacting with the fem Harry Potter character. Another theme is friendship. They build a strong bond that helps them face the challenges in the wizarding world.
A theme that is quite prevalent is the idea of belonging. The oc, who is an outsider in the world of Harry Potter at first, finds a sense of belonging with female Harry and her friends. Also, the theme of sacrifice can be seen. Sometimes, either the oc or female Harry has to sacrifice something for the sake of their relationship or the greater good in the wizarding world.
One common theme is the struggle of the vampire OC to fit into the wizarding world. Since vampires are not a common part of the Harry Potter universe, they often face prejudice and have to hide their true identity. Another theme is the power dynamic. Vampires are usually depicted as having unique powers, and how they use or misuse these powers in the context of the wizarding world is often explored.
One common theme is discovery. The Muggle girl discovers the wizarding world which is full of magic and wonder that she has never known before. For example, she might be amazed by spells and magical creatures.
Love and Romance are very common. Since it's about Sirius Black and an OC, the development of their relationship, from the first meeting to falling in love, is often a central theme.
In 'Harry Potter Muggle Nobility' fanfictions, a frequently seen theme is inheritance. The idea of inheriting not just magical abilities but also the status and responsibilities of Muggle nobility. Another theme is integration. How the Muggle noble elements integrate into the wizarding world. For example, in some fanfictions, Muggle noble traditions are incorporated into Hogwarts. Also, the theme of discovery is common. Characters discover the hidden Muggle noble side of the Potter family, which then leads to a whole new set of adventures and challenges.