One common theme is the struggle with acceptance. Both Caroline and Klaus have to accept the fact that they are going to be parents. For Caroline, it might be against her previous plans and for Klaus, it's a new concept as he has been mainly focused on power and revenge before. Another theme is the reaction of their friends and family. In many fanfictions, the characters in Mystic Falls are shocked and have different opinions about this unexpected pregnancy.
A sense of community or isolation can be a theme. Some fanfictions show them being isolated from the rest of the Mystic Falls gang because of their situation. Others show how they find a new community within themselves and with some unexpected allies. And of course, the theme of change. Both characters have to change a great deal in order to be good parents and partners, and this transformation is often at the heart of these fanfictions.
Love and protection are also common themes. Klaus, despite his dark past, will often show a very protective side towards Caroline and the unborn child. And Caroline, while initially scared, will grow to love Klaus more deeply through this shared experience. Also, the theme of fate vs. choice is often explored. Whether this pregnancy is some sort of fate for them or a choice they have to make to be together and raise the child is a big part of many stories.
Another theme is protection. Given the dangerous nature of their world, protecting the unborn child from various threats is often a central plot point. Enemies might try to harm the baby because of its potential power or to get revenge on Caroline and Klaus.
One common theme is the struggle between love and power. Klaus is often associated with power, and Caroline has her own strength. Their relationship in fan fiction often explores how love can either be a hindrance or a catalyst in the face of power dynamics. For example, in many stories, Klaus has to choose between his thirst for power and his love for Caroline.
One common theme is redemption. Klaus, who has a dark past, often seeks redemption through his relationship with Caroline in these fanfictions. For example, in many stories, he tries to change his ways for her.
There are also fanfictions where Klaus kidnaps Caroline as part of a deal or a bet. But as time passes, he finds himself intrigued by her strength and spirit. Caroline, on the other hand, uses this situation to try and figure out Klaus's weaknesses, which makes for an interesting power play between them.
It could lead to a whole new dynamic in the story. Maybe it would bring them closer or cause a lot of drama and complications.
In the fanfic, the pregnancy could be the catalyst for them to truly open up to each other. They might share their deepest fears and desires. Klaus could reveal his insecurities about being a father, fearing he'll be like his own father. Caroline could comfort him and they could bond over their hopes for the baby. As the pregnancy progresses, their love could grow stronger, and they could become a more united front against any threats.
One great fanfiction could be where Caroline and Klaus go on a journey to discover a hidden vampire lore that could change the fate of all vampires. It might involve them facing various challenges together and growing closer through the process.
One common plotline is the struggle with their relationship. Since Klaus is a complex and often villainous character in the show, there's a lot of drama around how they'll raise the child together. For example, Caroline might be worried about Klaus's violent tendencies influencing their baby.
Klaus would be very attentive to Caroline's pregnancy cravings. He'd see it as his duty to take care of her during this time. He might cook for her himself if he can, or take her to the best restaurants to get what she wants. He would be a bit overprotective too, making sure that whatever she eats is of the highest quality and safe for her and the baby. He'd also listen intently to her when she talks about her cravings, finding it endearing and a sign of the new life growing inside her.
Klaus might be overjoyed. He has always been attracted to Caroline, and having a baby with her could be the ultimate sign of their connection. He would probably be very protective, using all his power and resources to keep her and the unborn baby safe.