Tom Hardy could also be a good option. He has a great presence on screen and can be very intimidating when needed, but also show vulnerability. This would work well for a character like Blaise Zabini's dad who may have a lot of secrets and different sides to his personality.
Maybe Chiwetel Ejiofor. He has shown in his previous roles that he can play complex characters with a lot of emotional range. For this role, he could bring out the more ambiguous nature of Blaise Zabini's dad, whether he's a good guy or a bad guy or something in between.
One possible fanfiction could be about Blaise Zabini's dad's mysterious past in the wizarding world and how it might intersect with Harry Potter's journey. Maybe his dad was involved in some secret magical society that Harry later discovers during his fight against Voldemort.
Their relationship could start with distrust. Harry has been through a lot with the Slytherins, and Blaise Zabini's dad has a reputation in Slytherin. But as they are forced to work together on a school project or to solve a mystery at Hogwarts, they begin to see each other in a new light. Maybe Blaise Zabini's dad shows a side of himself that is more caring and less of the typical Slytherin stereotype, which makes Harry reevaluate his views.
One idea could be that Blaise Zabini's dad was a close friend of Sirius Black in their youth. When Harry Potter starts to explore Sirius's past, he stumbles upon Zabini's dad and uncovers a story full of friendship, betrayal, and a long - lost magic that could change the course of the wizarding world again.
One idea could be that Blaise Zabini's dad was a secret agent for the Order of the Phoenix all along. He could have been spying on the Death Eaters from within their ranks and using his family's reputation to gain their trust. This would add a whole new layer of mystery and intrigue to the story.
A possible plot for this fanfiction could be that Blaise Zabini's dad was a double agent during the first wizarding war. Harry finds out about this when he starts to investigate some strange occurrences at Hogwarts that seem related to the past. This discovery leads to a series of events where Harry has to trust Blaise, despite their differences, to uncover the truth. Along the way, they might also learn more about their own families and the secrets they have been hiding.
One common theme is friendship. Since they are from different houses (Harry from Gryffindor and Blaise from Slytherin), exploring how they overcome the house rivalries to form a bond is often seen. Another theme is mystery. Blaise has an air of mystery about him in the original series, and fanfictions often expand on that, like exploring his family secrets. Also, self - discovery is a theme, as both characters grow and learn more about themselves through their interactions.
Often, they explore the contrast between Harry's more well - known and heroic persona and Blaise's rather mysterious and slytherin - like nature. Their relationship in these fanfictions is usually about finding common ground.
One great fem Harry Potter and Blaise Zabini fanfiction is 'The Unexpected Bond'. It shows a unique relationship developing between them in the Hogwarts setting. The author does a wonderful job of portraying fem Harry's character with newfound femininity while still maintaining her strong will.
Power and politics are often themes in Blaise Zabini Harry Potter fanfic. Given his family's position in the wizarding world, Blaise can get involved in power struggles or political intrigues. Some fanfics depict him as a key player in the wizarding politics, either trying to maintain the status quo or bring about change. Another theme is loyalty, whether it's his loyalty to his family, his house, or his newfound friends.
One great 'Harry Potter Blaise Zabini' slash fanfic is 'The Unlikely Bond'. It beautifully explores their relationship in a way that stays true to the Hogwarts setting. The character development is well - done, and it has some really engaging plot twists.