The plot could revolve around Harry's struggle to fit in. Since he is a demigod raised by Bellatrix, he is likely to be an outcast in both the wizarding and demigod communities. The wizarding world may not understand his demigod powers and the demigod world may not accept him because of his connection to Bellatrix. He might have to go on a journey to find others like him or to find a place where he truly belongs. Along the way, he could face many challenges and enemies, both magical and perhaps related to his demigod status.
His character development could be a long and complex process. At first, he might be obedient to Bellatrix due to her being his caregiver. But as he discovers more about his demigod side, he could start to question her teachings. He might become more independent and start to form his own moral code. For example, he could learn about the demigod concept of balance and try to apply it to the wizarding world, which is often filled with black - and - white views of good and evil. This would lead to him having a more nuanced view of the world around him.
One idea could be that Harry discovers his demigod powers in a world where Bella is his caretaker. Maybe he has powers related to fire, and Bella has to help him control it so he doesn't accidentally set things on fire. For example, they could live in a small village where Harry's outbursts start to draw unwanted attention.
The plot could involve Harry growing up with Bella and slowly realizing he's different. For instance, he might be stronger and faster than the other kids in their neighborhood. As he gets older, strange things start to happen around him, like plants growing abnormally fast when he's angry. Bella then decides it's time to tell him about his demigod nature.
If Harry Potter was raised by Bellatrix, he would likely grow up in a very dark and twisted environment. Bellatrix is a Death Eater, so Harry would be exposed to the dark arts from a young age. His values and beliefs would be very different from the ones he has in the original story. He might not have the same sense of right and wrong, and could be more inclined towards the use of dark magic.
One possible storyline could be that Bellatrix, despite her dark past, has a change of heart due to some magical influence or a deep - seated love for the Potter family. Sirius, of course, would be a positive influence. They might raise Harry in a more unorthodox way, teaching him both light and dark magic in a balanced way so he can understand the full spectrum. This could lead to Harry being a more powerful and empathetic wizard, able to bridge the gap between different magical factions.
Harry would likely learn dark magic. Bellatrix is a master of the dark arts, so she would teach Harry curses and hexes that are not typically taught at Hogwarts. He might learn how to use the Cruciatus Curse effectively, for example.
If Harry was raised by Bellatrix, his character would likely be much darker. Bellatrix is a Death Eater, so Harry would be exposed to dark magic and Voldemort's ideology from a young age. He might be more ruthless and less empathetic compared to the Harry we know. For example, he might not value friendship as highly since Bellatrix doesn't really understand the concept of true friendship. Also, his view of the wizarding world would be skewed towards the pure - blood supremacist ideas that Bellatrix adheres to.
The challenges would be numerous. Socially, he would be an outcast among those who oppose the Dark Arts. His magical education would be limited to Bellatrix's knowledge, which is mainly centered around dark magic. This could put him at a disadvantage when dealing with more complex and positive forms of magic. Emotionally, he would lack the warmth and support that a normal family provides, and this could lead to serious psychological issues.
The story would be drastically different. Harry might not oppose Voldemort. He'd be on the 'dark side' instead. His Hogwarts experience would be non - existent or very different if he even went there. He'd probably use the dark arts more often.