One common theme is family loyalty. The sisters often have to stick together in the face of the many threats in the vampire - filled world. Another is power struggles. The sisters may have unique powers that others want to control or use for their own gains.
The theme of redemption is often present too. If a sister has made mistakes in the past, she may try to redeem herself in the eyes of her family and the community. Also, the theme of mystery is common, as there are often secrets about their past or their powers that need to be uncovered.
One common theme is loyalty. Sisters in the fanfiction often show unwavering loyalty to each other despite the supernatural challenges they face. Another is sacrifice. They might be willing to sacrifice their own happiness or safety for their sister. For example, in many stories, a sister will put herself in danger to protect her sibling from a vampire or a witch's curse.
Love is also a common theme. It could be romantic love for her character or platonic love within the family. In some fanfictions, Klaus's sister falls in love with a character from the show, and this love story is intertwined with her relationship with Klaus. For instance, in 'Love and Blood', her love interest is a werewolf, which creates a lot of drama considering the vampire - werewolf dynamic in the Vampire Diaries.
One common theme is her struggle to fit into the world that has been turned upside down by the presence of vampires. She often has to deal with the danger that vampires pose to her and her loved ones while also trying to understand their complex nature.
One common theme is the struggle for self - identity. Since the sister is compelled, she often has to fight against the actions she's forced to do and figure out who she really is outside of the compulsion.
Often, it can be a theme related to the exploration of forbidden or controversial relationships. In some fanfictions, the act of spanking might be used to symbolize a deeper, more complex emotional connection between the sisters. It could also be a way to add a bit of shock value and draw readers in, especially when exploring the darker or more edgy aspects of the Vampire Diaries world and the relationships between the sisters.
A common plotline is the sister's adjustment to the new world she's come back to. Things might have changed a lot since she died, like new vampire lords or different witch covens in control.
Themes usually include the struggle with identity. In a world full of supernatural beings, a pregnancy can make a character question who they are and what they want to pass on to their child. Also, there's often a theme of sacrifice. The mother or father might have to sacrifice their own desires or safety for the sake of the baby. It's like in some fanfictions where a character gives up their vampire powers to ensure a normal life for their unborn child.
One common theme is Kol's struggle for acceptance. Since he's often seen as the 'bad boy' in the Vampire Diaries, many fanfictions explore his desire to be understood and accepted by others. Another theme is his relationships, whether it's romantic relationships or his complex family dynamics. For example, his interactions with his siblings are often a big part of the stories.
One common theme is love and relationships. OCs often find themselves falling in love with the main characters from the show or other OCs. It adds a new layer of romantic drama to the already complex world of the Vampire Diaries.
Love and family are also prevalent themes. The mpreg situation usually brings the characters closer together in unexpected ways, forming new family units or strengthening existing ones. For example, a character who was previously a loner might find a new sense of belonging because of the pregnancy. It's also about how love can overcome the challenges presented by this unique situation.