A human could also be a love interest. The Salvatore sister might be intrigued by the simplicity and innocence of a human life. This relationship would be complex as she has to hide her true nature from the human, and also protect him from the other supernatural beings in Mystic Falls.
Klaus Mikaelson is often paired with the Salvatore sister in fanfiction. His complex character and the power dynamics between them can lead to some really engaging storylines. Elijah Mikaelson is also a popular choice. His noble and protective nature can be a great contrast to the Salvatore sister's more fiery or independent personality. Tyler Lockwood might also be a good pairing, especially if the fanfiction focuses on the werewolf - vampire dynamic in the Vampire Diaries universe.
A common plotline is the Salvatore sister coming back to life after being thought dead for a long time. This brings a lot of drama as her brothers have to adjust to having her around again. Also, she might be a hybrid, part vampire and part something else. This gives her unique abilities and makes her a target for different factions in the story. Many fanfictions explore how she deals with her new identity and the powers that come with it.
Perhaps the Salvatore sister was turned into a vampire long before her brothers, and she has been in hiding all this time. When she finally reveals herself, she has a whole different set of vampire ethics compared to them. She could teach them new ways of co - existing with humans without causing too much harm, which would lead to a lot of interesting interactions within the Mystic Falls community.
In this type of fanfiction, Eric is a very likely love interest. He was already interested in Sookie when she was human, and now that she's a vampire, they might have a deeper connection. Bill, on the other hand, may have a love - hate relationship with Sookie. He could be jealous of her new vampire status. There could also be a non - vampire love interest, like a werewolf who is attracted to Sookie's newfound strength and independence as a vampire.
There could be a non - Supernatural character as a love interest as well. Maybe a human who has some connection to the world of the supernatural through a family curse or something similar. This human could see Lilith's sister for who she truly is, not just as a demon, and they could develop a relationship based on mutual understanding and acceptance outside of the usual hunter - demon - angel dynamics.
Stefan Salvatore is one of the main characters in the Vampire Diaries novel. He is a vampire with a complex personality. He struggles with his vampire nature, often trying to resist his baser instincts. He is in love with Elena and his relationship with her is a central part of the story.
Jacob could be a potential love interest. He's a werewolf, and his connection to Sam's pack could bring an interesting dynamic. Their relationship could start off as a friendship based on mutual understanding of the supernatural world, and then develop into something more romantic over time.
One great Damon Salvatore fanfiction is 'A Different Kind of Love'. It delves deep into Damon's complex character, exploring his relationships in a new light. The story has a great plot that keeps you hooked from start to finish.
Perhaps a mortal with a special gift for metallurgy or some other craft related to Hephaestus' work. This mortal could be seen as an equal in terms of skill, at least in a way that catches Hephaestus' eye. They would bond over their shared love for the craft, and over time, this bond could turn into a deep, loving relationship. Hephaestus might be drawn to the mortal's unique perspective and the way they approach the craft despite not having the same divine powers as he does.
One common theme is family. Since the Salvatores are brothers, their relationship as humans is often explored, like how they support or conflict with each other. Another theme is love. Their relationships with female characters, like Elena, might be different as humans. And there's also the theme of mortality. As humans, they face the reality of death, which is a big contrast to their vampire selves.