Well, it would be a lot less antagonistic. Without the whole Death Eater past and the spying for Dumbledore while seeming to be on Voldemort's side, Snape wouldn't have that built - up resentment towards Harry. He might actually see Harry as a talented young wizard worthy of proper mentorship, instead of constantly being so harsh on him.
The relationship would start off rocky. Snape would be resistant to Harry's kindness as he has always seen Harry as James Potter's son. But Harry's persistent efforts to understand and help Snape would gradually break down Snape's walls.
Well, it would be a lot more complex. Instead of the animosity that exists in the original story, there could be an underlying bond. Snape might be more protective of Harry from the start, but still struggle to show it in a positive way. Harry, on the other hand, might be more curious about Snape and try to understand him better.
It would be extremely complex. Harry might initially be in disbelief and struggle to accept Snape as his father. Snape, on the other hand, would probably be very strict but also deeply protective in his own way.
In many fanfictions, the relationship between Severus Snape and Harry Potter is complex. Some explore Snape's underlying protectiveness of Harry, which was initially hidden due to his own grudges and the need to maintain his cover. This could be seen as a form of redemption for Snape, as he was in love with Harry's mother. The fanfictions often play with the idea of how their relationship could have developed differently from what was shown in the original books.
A really interesting plot twist could be that Snape discovers a new form of magic. Since he's not involved with Voldemort's dark arts, he has more time and mental energy to explore other areas of magic. Maybe he stumbles upon a long - lost magic that can counteract the most powerful dark curses. This discovery could change the balance of power in the wizarding world, making it so that Voldemort's rise is not as inevitable as it seemed in the original story.
In a fanfiction scenario, Harry's actions could cause a complete breakdown in any potential for a positive relationship between them. Snape's loyalty to Dumbledore and his role in protecting Harry from the shadows would be put at risk. Harry would have to face the fact that he may have made a huge mistake. And Snape, who has sacrificed so much already, would be in an even more precarious position, both with Voldemort and in the wizarding world in general. This could lead to a chain of events that completely alters the course of the wizarding war, with far - reaching consequences for both Harry and Snape.
In some fanfictions, Snape's relationship with Harry is shown as more of a father - son relationship. For example, in 'A Different Kind of Bond', Snape takes Harry under his wing early on, and they develop a mutual respect. This is very different from the strained relationship in the books.
Snape's character changes in his relationship with others too. He becomes more involved with the Hogwarts community as he is now responsible for Harry. He might start to collaborate more with other teachers, like McGonagall, who he previously had a rather cold relationship with. His attitude towards the students also changes as he realizes that they are just kids trying to find their way, much like Harry. This is a big shift from his usual strict and often unforgiving self.
Another way is if there was a magical accident that forces Harry and Snape to rely on each other. For example, they are trapped in a magical realm where only by combining their unique magical abilities can they escape. During this time, they have to put aside their differences and work together. Harry learns about Snape's past traumas and Snape sees Harry's courage and determination up close, which changes their relationship for the better.
One unique aspect is the exploration of Snape's double - agent status. Fanfictions often dig deeper into how he managed to deceive Voldemort for so long. For example, some stories might focus on the spells or mental techniques he used.