In some fanfictions, Harry might come to understand Snape better and they could develop a grudging respect for each other. Harry realizes all that Snape sacrificed in the war and how he was on the good side all along.
At first, it's likely to be tense. Harry has years of seeing Snape as a bully. But as they start living together, they begin to understand each other. Snape might show his more vulnerable side to Harry, like his memories of Harry's mother. Harry, in turn, starts to respect Snape's knowledge and sacrifice. Eventually, they develop a bond like a father - son relationship.
Sure. Fanfiction often takes existing characters and gives them new storylines. Maybe in some fanfictions, a situation arises where Harry and Snape have to work together towards a common goal, like saving Hogwarts from a new dark threat. Through this shared experience, they could come to respect and like each other, thus becoming friends.
Yes, it could be possible in fanfiction. Fanfiction allows for wild reinterpretations of the source material. Maybe there could be a story where a dark wizard in the past manipulated their family trees so that Harry, Snape and Voldemort are unknowingly brothers. It would make for a very interesting plot, full of drama and conflict as they are on different sides in the original story.
One possible reason could be Snape's long - standing grudge against James Potter, Harry's father. Since Snape had a difficult past with James, he might project that onto Harry. Another reason could be that Snape is trying to protect Harry in a very strange way. He may think that by rejecting Harry, he is keeping him at a distance from the dangerous wizarding world politics and plots that Snape is often involved in.
One possible motive could be that Snape is still deeply influenced by his loyalty to Voldemort in this fanfiction. Maybe Voldemort has some hold over him that forces him to do the unthinkable. Another reason could be a misunderstanding. Snape might believe that Harry has turned to the dark side or is about to, and he decides to take preemptive action to stop what he thinks will be a great evil.
In certain fanfictions, Harry could be the one to reach out to Snape. He might feel a sense of indebtedness towards Snape for his sacrifices. Snape, initially resistant, could eventually warm up to Harry's attempts at reconciliation. This could lead to a very different dynamic from their pre - war relationship, with them learning from each other and forging a new path in the post - war wizarding world.
Well, in fanfiction, the secret relationship might also involve some magical bond between Harry and Snape. Maybe a spell gone wrong or something that links them in a way that they have to keep it a secret. It could be that this bond makes them more empathetic towards each other's situations, with Harry realizing Snape isn't all bad and Snape seeing Harry as more than just James Potter's son.
One possible take on this fanfiction could be a story of redemption. Snape, who has always had a complex relationship with Harry, might find an unexpected alliance with Lucius in a situation where they all have to protect Harry from a greater dark threat. It could explore how their past enmities are put aside for a common goal.
Another characteristic is the exploration of their shared magical knowledge. Snape is a highly skilled wizard, and in fanfiction, he sometimes imparts some of his more esoteric knowledge to Harry. This creates a bond between them that wasn't as fully explored in the original series. Also, there are fics where they form an unlikely friendship, like when they are forced to team up against a common enemy and start to respect each other's skills and courage.
One possible reason could be that Snape shows a different side to Harry in the fanfiction. Maybe he protects Harry secretly from some hidden threats that others are unaware of, which makes Harry start to trust him.