Yes, there are some out there. You can start by looking on fanfiction websites like Archive of Our Own or FanFiction.net. Just search for 'Harry Potter is Sebastian Snape' and you'll likely find a variety of stories with different takes on this unique concept.
One possible plot could be that Harry discovers he has a hidden connection to Sebastian Snape, perhaps a long - lost family relation. This revelation could lead him to question his identity and his place in the wizarding world.
One great fanfiction could be 'The Summoning of Sebastian by Harry Potter'. In this story, Harry might summon Sebastian for a special mission. Maybe it's to solve a mystery in Hogwarts that only Sebastian's unique skills can help with. It could involve a lot of magical elements like complex spells and ancient artifacts.
In some fanfictions, Snape might use his advanced knowledge of potions to create a special concoction to heal Harry. He could draw on his skills in Herbology as well to find rare ingredients for the potion.
One more to consider is 'Snape: Beyond the Surface'. In this story, the author explores Snape's relationships with other characters like Dumbledore and McGonagall. It shows how his interactions with them were not always as straightforward as they seemed in the original books and adds more depth to his character.
One great Snape fanfiction is 'The Prince's Tale Redux'. It delves deeper into Snape's relationship with Lily. It shows his internal struggles and how his love for her influenced his actions throughout the series. It gives a more in - depth look at his character than what was shown in the original books.
In some fanfictions, Snape is indeed portrayed as Harry Potter's father. Fanfiction allows for creative reinterpretations of the original story, and this is one such interesting deviation from the canon where Snape's complex relationship with Harry takes on a whole new dimension.
Another possibility is a story set in an alternate universe where Harry Potter has the abilities of Sebastian Michaelis. He could use his newfound skills like superhuman strength and enhanced senses to solve mysteries at Hogwarts that are far more dangerous than the usual ones, like a hidden cult within the school that's performing dark magic.
In this kind of fanfiction scenario, Snape might initially be conflicted. On one hand, he has his long - standing dislike for James Potter, Harry's father. But on the other, his sense of duty as a Hogwarts professor could kick in. He might reluctantly start to heal Harry, all the while muttering under his breath about how much trouble Harry always seems to get into, just like his father. Then, as he heals Harry, he might start to see some of Lily, Harry's mother, in him and soften a bit.
One possible motive could be a misunderstanding. Maybe Snape is framed for something really bad, like a dark magic plot against Hogwarts. Harry, in his haste to protect the school and his friends, believes Snape is guilty and takes drastic action. Another reason could be if Snape accidentally endangers someone Harry loves dearly, like Ginny or Ron, and Harry's emotions get the better of him in the heat of the moment.