A theme that frequently shows up is redemption. Klaus, being a complex and often villainous character, may be on a path to redemption in some fanfictions, with Stefan either helping or hindering. Also, power dynamics play a role. Klaus is very powerful, and Stefan has his own set of abilities, so how they interact in terms of power is a common theme. For example, in some stories, Stefan has to find ways to level the playing field when dealing with Klaus.
One common theme is the clash of different vampire cultures. Since Stefan has his own vampire lore and the Twilight series has its own, seeing how they interact is often explored.
One common theme is redemption. Many fanfictions explore the idea of Katherine seeking redemption and how Stefan might be a part of that journey. Another is the theme of love and obsession. Their relationship was so complex in the show, and fanfictions often play with this idea, showing how their love or obsession for each other can change over time.
Love and sacrifice are common themes. Often, one of them has to sacrifice something for the other, like Stefan might sacrifice his safety to protect Caroline. It shows the depth of their love.
One common theme is the idea of eternal love. Since they are in a supernatural world, their love is often depicted as something that can transcend time and death. For example, in many fanfictions, even if one of them is in danger or seemingly lost, their love remains unwavering.
One common theme is friendship. Stefan and Bonnie often start as friends in the fanfictions. For example, they might be friends first and then face challenges that make their bond stronger.
One great 'Stefan and Klaus fanfiction' is 'The Bond Beyond Enmity'. It delves into how their complex relationship could develop in unexpected ways, like finding common ground in protecting Mystic Falls from a new threat. Another is 'A Different Alliance' which explores a scenario where they team up for a personal vendetta against a more powerful enemy.
One common theme is friendship. Often, the oc forms a deep and unexpected friendship with Klaus. Another theme is redemption. The oc might be involved in Klaus's journey towards redemption. For example, in some fanfictions, the oc helps Klaus face his past wrongs.
One common theme is redemption. When Klaus is hurt, it can be a starting point for him to seek redemption for his past wrongs. Another theme is vulnerability. It shows a side of Klaus that we don't always see, as he's usually portrayed as strong. For example, in some fanfictions, his hurt might make him more open to forming new relationships or mending old ones.
One common theme is love triangles. Since it involves Damon, Stefan and an OC, often there's a complex love situation. For example, the OC might be attracted to both brothers in different ways.
One common theme is loyalty. Their status as mates often means they have to be loyal to each other no matter what challenges they face, like in many fanfics where other vampires try to break their bond. Another theme is sacrifice. They might sacrifice their own desires or safety for the sake of their mate.