What could be the plot twists in fanfiction where Snape mentors Harry?

Well, a possible plot twist could be that Snape has a hidden identity or past that is only revealed after he and Harry get married. Maybe he is related to an ancient wizarding family that has a connection to Harry's own family history. Also, the way Ginny died could be a misdirection. It could turn out that she faked her death to escape some greater danger, and when she returns, she finds Harry married to Snape, creating a huge love triangle and a whole new set of complications in the fanfiction.

One possible plot could be that Bill mentors Harry in the art of ancient magic. Since Bill has been around for a while and has dabbled in many different areas of magic, he could introduce Harry to spells and magical knowledge that has been long forgotten. This could help Harry in his future battles or in his general understanding of the magic world.

The plot could take a really interesting turn when it comes to Voldemort. Since Snape is raising Harry, he might train Harry in a way that Voldemort doesn't expect. Maybe Harry would be more of a spy in the dark side's camp. Snape could also use his position to mislead Voldemort about Harry's true abilities and intentions. This would create a whole new set of challenges and power dynamics in the fight against the Dark Lord. Harry's loyalties would be constantly tested, and his relationship with Snape would be even more crucial to the story.

One possible plot twist could be that Snape saves Harry in a very public way, which shocks everyone in Hogwarts. Maybe Umbridge was about to use an illegal and extremely harmful spell on Harry during a public 'interrogation' session, and Snape steps in at the last moment, revealing some long - hidden information about Umbridge's true nature that even Dumbledore wasn't fully aware of.

One plot twist could be that Snape discovers a hidden secret about Harry's family that changes his whole perception of them. For example, he might find out that there was a prophecy related to Harry that was different from what everyone thought.

One plot twist could be that Snape discovers Harry is his son right before a major battle. This new knowledge gives him the extra motivation to fight even harder to protect Harry. Another could be that Voldemort finds out about this relationship and tries to use it against them both, perhaps by threatening to harm Harry if Snape doesn't turn on Dumbledore.

One possible plot twist could be that Snape blackmails Harry into joining a secret magical society at Hogwarts that Snape is leading. This society could be dedicated to protecting a powerful but dangerous magical artifact. Harry initially resists but realizes the importance of the cause as the story progresses.

One plot twist could be that Snape's true motives for being at Hogwarts are revealed to be more about protecting Harry all along. Another could be that Harry discovers some long - lost family magic that he can only access with Snape's help. Maybe there's a secret prophecy that involves both of them as uncle and nephew, and it changes the course of the war against Voldemort.

I really like 'Snape: Harry's Surrogate Father'. This fanfiction takes an interesting approach as it makes Snape into a father - figure for Harry. Snape's mentorship here is not just about magic but also about life lessons. He teaches Harry about love, sacrifice, and the true meaning of family. Another great find is 'Mentor Snape and Harry's Growth'. It shows how Snape's strict yet caring mentorship helps Harry to overcome his insecurities and become a more confident wizard, especially when dealing with his enemies at Hogwarts.

Their relationship develops in a rather interesting way. Snape, being a strict mentor, forces Harry and Draco to look past their differences. Harry begins to understand Snape's past and the reasons for his actions, which in turn makes him more open to Draco. Draco, who has always been in Snape's good graces to some extent, has to adjust to sharing Snape's attention with Harry. This causes some initial jealousy but later leads to a sort of rivalry - turned - friendship as they both grow under Snape's tutelage.