In the Harry Potter fanfiction, the 'thief of time' could be a character that has been overlooked or underestimated. It could be a young wizard who discovers a powerful but dangerous magic related to time. He might not fully understand the consequences of his actions and accidentally becomes the 'thief of time'. Or it could be a shape - shifter who uses different forms to steal time without being detected easily. They could be stealing time from important magical ceremonies or from the lives of key characters in the story.
An unknown wizard from a far - off land could be a thief in Harry Potter fanfiction. This wizard could come to Hogwarts or the wizarding world of Britain with the intention of stealing unique magical items that are not found in their own land. They would bring a sense of mystery and a new cultural perspective to the story.
It could be that he has been wronged by the wizarding society. So, in a form of rebellion, he decides to become a thief. He might steal from those who he thinks are corrupt or unfair. For example, if the Ministry of Magic has been unjust to him or his loved ones, he could target them or their allies. Another possibility is that he is influenced by a powerful and devious character who convinces him that stealing is a way to gain power or freedom.
In this Harry Potter fanfiction titled 'the thief of time', it could be centered around a mystery. The 'thief of time' might be a mysterious figure that no one can quite figure out. It could involve the characters like Harry, Hermione, and Ron trying to solve the mystery of who this thief is. They might have to explore different time periods in the wizarding history, using spells like the Time - Turner, to find clues and stop the thief from causing more chaos in the world of magic.
The obvious enemies could be the Ministry of Magic. If Harry is stealing things, even if for good reasons, they would see him as a criminal. The Aurors would be sent after him. Another potential enemy could be some of the dark wizards who might want the same items that Harry is after. They would not want Harry to get in their way and would try to stop him or even capture him to get information on the whereabouts of the valuable items.
The plot could involve a young wizard who has a talent for thievery but a good heart. He meets Harry Potter during a time when Hogwarts is facing a new threat. The thief friend uses his skills to steal a dark magic item that was being smuggled into the school. Along the way, they face challenges from other dark wizards who want the item for themselves. Harry and his thief friend have to work together to keep the item safe and figure out how to destroy it.
In some fanfictions, Harry Potter could potentially be depicted as a 'good thief' in a rather unorthodox sense. For example, if he's stealing something for a noble cause like stealing a powerful artifact from a dark wizard to prevent it from being misused. But in the original canon, he is not a thief.
It could be the thief of time themselves. We could get to know their motives, their daily life of stealing time, and their inner thoughts. It would be a very unique perspective.
One popular 'Harry Potter' thief fanfiction could be about a character stealing magical artifacts from Hogwarts. Maybe it's a student who feels wronged by the school system and decides to take matters into their own hands in a rather unethical way. For example, they might steal a powerful potion ingredient that was going to be used for a very important experiment in Potions class, which then causes chaos as the teacher tries to find out who did it.
Perhaps the thief is a corrupted official in the Yugioh tournament world. He uses his position to steal valuable cards from the best duelists at night. He believes that by having these cards, he can control the outcome of important tournaments and make a lot of money through illegal gambling on the duels. But his actions start to draw the attention of some of the more ethical characters in the Yugioh universe, and they begin to investigate.
Sirius Black could be a trainer. Sirius, being Harry's godfather, would be highly motivated to train Harry. He could use the time - turner to go back to a time when he was at his peak in terms of combat skills and pass on his knowledge to Harry, especially in the areas of dark - wizard fighting and survival skills.