In this fanfiction, it could be about a philosophical difference. Lily Potter might have a different view on how to deal with the threat of Voldemort. Dumbledore is often very strategic and calculating, while Lily could be more impulsive and driven by her emotions and motherly love. So, they could be at odds over how to train Harry or which allies to trust in the fight against the Dark Lord.
Perhaps it's a story of redemption for Dumbledore. Lily Potter, having passed away, comes back in some form (maybe as a spirit) and confronts Dumbledore about his past mistakes. She forces him to face his actions regarding the Gaunt family, his relationship with Grindelwald, and how those things have indirectly affected her family. This could lead to Dumbledore re - evaluating his decisions and making amends in the fight against Voldemort.
For Lily Potter, her husband James Potter might be a likely ally. He would support her in any conflict she has with Dumbledore. Also, her close friends from her school days could side with her. They know her well and would trust her judgment.
It's really hard to say. Dumbledore is known for his vast magical knowledge and powerful spells. However, Lily Potter was also a very talented witch. If we consider her love - based magic, like the protection she cast on Harry, it could be extremely powerful. In a direct magical duel, Dumbledore might have the upper hand in terms of experience and a wider range of spells, but Lily's love - fueled magic could be unpredictable and potentially very strong.
Another plot could involve a time - travel scenario. Lily Potter travels back in time and encounters a younger Albus Dumbledore. Their ideologies clash as Lily, coming from a different era, has different views on how magic should be used and how the wizarding world should be run. This could lead to a series of events where they have to either work together or oppose each other depending on the situation.
It could be that after a series of events that make Harry question his own judgment, he submits to Dumbledore's authority. For instance, if there are false prophecies or misinformation floating around that lead Harry astray. Dumbledore, with his greater experience and knowledge, helps Harry see the truth. So Harry decides to submit to Dumbledore in order to get back on the right track and protect Hogwarts and the wizarding world.
One possible plot could be that Dumbledore has been possessed by a dark entity. Under its influence, he kidnaps Hermione thinking she has some knowledge or power that the entity wants. Hermione then has to use her wits to try and break Dumbledore free from the possession while also trying to escape.
One possible reason could be a misunderstanding. Maybe Harry overheard something that made him think Dumbledore was planning something against him that he didn't understand. For example, if he heard Dumbledore discussing a dangerous mission for him without his full knowledge.
In such a fanfiction, one possibility could be that Harry Potter defies Dumbledore over the use of certain dark magic items. Maybe Harry believes that Dumbledore is being too cautious and that these items could be used for good in the fight against Voldemort. For example, he might think that the Elder Wand could be harnessed in a different way than Dumbledore anticipates.
I'm not sure if there is a specific 'Harry Potter Dumbledore Stealing Fanfiction' out there. However, if there were, the plot could potentially involve Dumbledore stealing something important like a powerful magical artifact that he believes is necessary to protect Hogwarts or the wizarding world from a great evil, but his actions are misinterpreted by the characters in the fanfiction.
In a fanfiction, Dumbledore might steal out of desperation. Suppose there was a situation where a curse was about to be unleashed on Hogwarts, and the only way to stop it was by stealing a particular ingredient for an antidote from a place where it was not supposed to be taken. Dumbledore, seeing no other option, decides to steal it. His motive here is to save the school and its students, even if it means breaking the rules.
One possible plot could be that Dumbledore wants Harry to take on a dangerous but crucial mission earlier than in the original story. He might be desperate because he sees a dark threat approaching faster and believes only Harry has the unique power to stop it.