One plotline could involve a dark force in the wizarding world that is interested in Harry's new vampire state. Snape and Harry would then have to work together to fend off this threat. Along the way, their relationship could grow from an initial awkwardness or even animosity (due to their past) to a deep and loving bond. There could also be sub - plots about Harry learning to control his vampiric urges, like the thirst for blood, and Snape helping him with that using his potions knowledge.
A possible plotline could be Harry's struggle with his new vampire identity. He might have to hide it from his friends at first. And Snape, being his mate, could be the only one who truly understands what he's going through. Another plotline could be the two of them facing opposition from the wizarding community because of their unusual relationship.
One possible plotline is that they are all framed for a crime they didn't commit. To clear their names, they must team up. Harry's quick thinking, Snape's ability to deceive when needed, and Lucius's connections all play a part. As they work together to find the real culprit, they form a bond of mutual trust and respect, which is the foundation of their new - found mate - ship.
There are definitely some 'Vampire Snape Mate Harry' fanfictions. However, the quality can vary greatly. Some might focus more on the relationship aspect between Snape and Harry in this unique vampire - themed setting, while others could involve more complex plotlines with other characters from the Harry Potter universe getting involved in their relationship.
One common theme is the forbidden love aspect, as Snape and Harry have a complex relationship in the original series. Another could be the power dynamics, especially with Snape being a vampire and how that affects his relationship with Harry.
One possible plotline could be that Snape accidentally discovers Harry is extremely ticklish and uses it as a form of mild punishment when Harry misbehaves in Potions class. For instance, if Harry forgets an ingredient or causes an explosion.
Maybe in a fanfiction, Harry could be framed for something he didn't do, and Snape, believing the false accusations, smacks him in a moment of anger. This could then lead to a series of events where Harry tries to prove his innocence and Snape has to come to terms with his hasty action. Another plotline could be that Snape is under the influence of a dark spell that makes him act out of character, and Harry just happens to be in the wrong place at the wrong time and gets smacked.
One possible plotline could be that Harry discovers Snape's memories early on. Overwhelmed by the truth of Snape's love for his mother and his selfless sacrifices, Harry hugs Snape as a sign of immediate forgiveness and gratitude. Another could be in a post - war scenario where Snape is still alive, and Harry, now a more mature wizard, reaches out to Snape to heal old wounds.
One possible plotline could be that Harry discovers his unique connection to Severus and Lucius and has to deal with the secrecy and the implications within the wizarding world. There might be a lot of internal conflict as he tries to understand his feelings for both of them while also facing the judgment of others.
A plotline might also involve Harry's relationships changing. As a girl, his/her romantic relationships could take a different turn. The pregnancy could add an extra layer of complexity. For example, if there was a previous romantic interest in a female character, that dynamic could shift completely. Also, there could be a sub - plot about how the wizarding society views a pregnant, transformed Harry, and the challenges he/she faces in a world that has certain expectations and norms.
Another plotline could be that there is a spell or a magical occurrence that forces Snape and Harry to be close to each other. Initially resistant, Snape eventually gives in and cuddles Harry. This could then be the start of a journey where they learn to trust and rely on each other more.
The letter might be a summons to a secret wizarding council. Harry Snape's journey to deliver it could involve him facing his own inner demons as well as external obstacles. He might have to pass through dangerous terrains and encounter magical beings that are either trying to stop him or help him depending on their own agendas. As he gets closer to his destination, he discovers more about the true nature of the council and his role in the wizarding world.