His character development would be extremely different. He would no longer be the 'chosen one' in the traditional sense. He might feel a sense of shame or guilt that he didn't have before. His self - confidence would take a huge hit. He would constantly be looking over his shoulder, wondering if people were judging him based on his father. His magic might also change. He could have an easier time with some of the more complex and darker spells, but at the same time, he would have to be extra careful not to let that power corrupt him. His moral compass would be all over the place as he tries to reconcile the fact that he is the son of the most evil wizard with his own desire to be a good person.
Well, he might become more confident and self - assured. After all, defeating the most powerful dark wizard of all time is no small feat. He could also be a bit more somber, having seen the true horrors of the dark side up close.
Harry's character would develop very differently. In the original series, he was an orphan with a sense of loneliness. But as Cersei's son, he would be in a position of power from the start. He would be groomed for leadership in Westeros. However, his experiences at Hogwarts would introduce him to a different kind of community. His relationships with his classmates would be strained at first due to his family's reputation. But over time, he could learn to be more empathetic and use his power to bring about positive change in both Westeros and the wizarding world, breaking away from some of the more negative Lannister traits.
Harry would be more open to dark magic. Since Voldemort is his adoptive father, he would be exposed to different aspects of magic earlier. He might not have the same fear of the dark side as in the original story. For example, he could be more confident in using spells that are considered dark but for good reasons, like using the Imperius Curse to stop a criminal.
He develops a more rebellious streak. In the original, Harry was quite respectful of authority in the wizarding world. But being raised by bikers, he might question rules more often. For example, he might not be as quick to follow Hogwarts' strict regulations.
When Harry is in Slytherin in fanfiction, his view of the wizarding world may change. He may start to see the grey areas more clearly. Instead of seeing things as simply good or bad, he realizes that there are many factors at play. This makes him more complex as a character. He may also have to deal with the Slytherin legacy of the Dark Arts. He has to navigate through the temptations and warnings related to it. He might study some Dark Arts spells not to use them for evil, but to understand how to defend against them, which is a very different path from what he would have taken in Gryffindor.
In this fanfiction, Harry's development would deviate a lot from the original. His sense of right and wrong would be blurred. Since he's raised by devils, he may not have the same values as the normal Harry. He could be more self - centered, focused on his own survival and power gain rather than the well - being of others. His magical abilities might also develop in a more unorthodox way. Instead of learning the traditional spells for good, he might learn spells that are more harmful or controlling.
He'd likely be more inquisitive about different forms of magic. Instead of just relying on the spells taught at Hogwarts, he'd constantly seek out new magus - based knowledge.
If Voldemort was already dead in the fanfic, the characters would develop in very interesting ways. For instance, Neville would not have to find his courage in the face of Voldemort. He could develop his skills in Herbology more freely and perhaps become a renowned expert in the field much earlier. Luna Lovegood could explore her unique brand of magic and beliefs without the overshadowing of the Dark Lord. The Weasley family would be more at ease, and Fred and George could focus on their joke shop business without the fear of Voldemort - influenced regulations or attacks.
Harry would likely become more feared by some in the wizarding world. Since the Basilisk is often seen as a terrifying and dangerous creature, his connection to it might make others view him with suspicion. He would also have to grapple with the darker side of magic that the Basilisk represents, which could make him more brooding and introspective.
His magical abilities might develop in a different way. The Malfoys could introduce him to different types of magic or magical artifacts. Maybe he'd learn more about the Dark Arts in a different context, not for evil purposes but just to understand it better. He could also become more skilled in areas like Occlumency earlier on, since the Malfoys might see it as an important skill to protect their family secrets. His relationship with his Gryffindor traits would be tested. He might still have his bravery, but it could be expressed in different ways, like standing up to the Malfoy family's wrongdoings.