Another plotline might involve the Potter twins uncovering some long - hidden secrets about Snape's past. They could discover things that make them see him in a whole new light, and this new understanding could change their relationship and the course of events at Hogwarts. For example, they might find out about his unrequited love for their mother in a different context.
A possible plotline could be the Potter twins getting into trouble and Snape being the one to save them, not out of any love for them at first, but because of his sense of duty. As he spends more time with them during this process, he gradually develops a more paternal or protective feeling towards them, which is quite a contrast to his usual cold exterior.
One interesting plotline could be Snape taking on a mentoring role for the Potter twins in a more in - depth way than in the original series. Maybe he teaches them some advanced potions techniques or helps them understand the darker aspects of magic that others might shy away from.
Another plot could involve the child having special powers or a unique connection to the magical world because of Snape as their father. For example, they might have an extraordinary talent for potions, like Snape, and this draws the attention of both good and bad wizards. It could create a story full of adventure as the child is caught in the middle of different factions vying for their loyalty.
A great plotline might be that Snape adopts Harry secretly at first. Harry starts to notice some changes in his life, like getting better study materials and more personal attention in his magical education. As time goes on, Snape has to face his own demons while raising Harry. He might struggle with his past hatred for James Potter while seeing James in Harry. At the same time, Harry could be trying to figure out why Snape is being so nice to him all of a sudden, which could lead to a journey of self - discovery for both of them.
One interesting plotline could be Snape and Harry having to work together on a secret project for Dumbledore. They start off distrusting each other but as they face challenges, they gradually become friends. For example, they might be researching a powerful dark magic spell that Voldemort is after, and in the process, they learn about each other's past traumas and start to empathize.
Some fanfictions have a plotline where Snape survives the Battle of Hogwarts and he and Harry have to deal with the aftermath together. They might have to face the wizarding community's reaction to Snape's past actions and also work on rebuilding Hogwarts. There are also stories where Harry, while still at school, starts to understand Snape's difficult position between Dumbledore and Voldemort and tries to help him in some way, which creates a whole new dynamic between them.
One interesting plotline could be Harry growing up with Snape's guidance and inheriting his potions skills at an early age. He might have a different dynamic with the other Hogwarts students, being more of an outcast due to his connection to the often - misunderstood Snape.
A great plotline might be Snape teaching Lily Luna Potter some of his signature potions in a private tutoring session. Through these interactions, they develop a unique bond. Or perhaps Lily Luna Potter gets into a dangerous situation, and Snape is the only one who can save her because of his in - depth knowledge of the dark arts. This would create a scenario where she has to trust him completely, despite his often - misunderstood reputation.
In some fanfictions, their twin status might change the way the Sorting Hat sorts them. Instead of Harry going to Gryffindor, perhaps they both end up in Hufflepuff because of their shared values that are more in line with that house. This could lead to a completely different story arc where they are known for their loyalty and hard work rather than Harry's typical Gryffindor - like heroics. Also, their family relationships would be different. The Dursleys might have to deal with two magical children instead of one, which could change the way Harry (and Neville) grow up and view the Muggle world.
One interesting plotline could be that they discover their twin relationship early on and try to keep it a secret from everyone at Hogwarts. They might secretly help each other out in classes and with their rivalries against other houses.
A possible plotline is their different magical abilities. Percy might be really good at transfiguration and charms, while Harry has his natural talent for defense against the dark arts. They could compete in a friendly way, but also learn from each other. For instance, Percy could teach Harry some advanced transfiguration spells, and Harry could show Percy some new defense techniques he learned from his experiences.
One interesting plotline could be the Carrow twins trying to manipulate Harry into joining their dark deeds, but Harry resists and tries to turn them to the good side. Another could be Harry forming an unexpected friendship with one of the twins that causes a rift between the twins themselves.