Well, Harry Potter is a given. Among the Malfoys, Draco will play a significant role as he and Harry will have to co - exist in a new family dynamic. Narcissa Malfoy will be like a mother figure to Harry, and her character development in relation to Harry can be very interesting. There could also be appearances from other Hogwarts professors who might interact with Harry in this new situation, and they could either support or be skeptical of the Malfoys' adoption of Harry.
Obviously, Harry Potter is the central character. Then there are the Malfoys - Lucius, Narcissa, and Draco. Hermione and Ron might also be involved, perhaps as characters who are initially suspicious of Harry's new situation but later come to understand it.
I think Dobby could also be a significant character in this fanfic. Since he has connections to both the Malfoys and Harry. He might be the one who gives the Malfoys the idea to rescue Harry or helps in the rescue in some way. Also, Voldemort or his Death Eaters could be important in the background as the threat that Harry needs to be rescued from. Their presence would constantly loom over the story, making the Malfoys' actions more dangerous and significant.
Well, obviously the main character is the one who is adopted by the Malfoys. They are often an original character created by the fanfic writer. Then there are the Malfoy family members like Lucius, Narcissa, and Draco. Lucius is usually portrayed as the strict, traditional pure - blood father figure. Narcissa is the more complex mother, who may have a softer side towards the adopted child. And Draco, who can be a rival or a friend to the adopted character depending on the story.
The main characters would be Hermione and the Malfoys. Hermione, being the intelligent and strong - willed Gryffindor. Among the Malfoys, Draco would be at the forefront. He has his own insecurities and growth arc that can be intertwined with Hermione's stay. Narcissa could act as a mediator of sorts between Hermione and the more hostile members of the family like Lucius, who might initially see Hermione as a threat to their pure - blood ideals.
Obviously, Harry Potter himself would be a main character. Then, there would probably be members of the Potter family, like his adoptive parents. Also, characters like Dumbledore might still play important roles as he often has a hand in Harry's life.
Obviously, Harry Potter himself is a main character. And then there would be the Daedra who adopt him. Depending on which Daedra are involved, they would each have their own personalities and motives. For example, if it's a powerful and manipulative Daedra, it could be a major source of conflict for Harry.
Obviously Gibbs himself would be a main character interacting with Harry. He'd be like a father figure.
Obviously, Harry would interact a great deal with Newt. But also, they might run into other characters like Hagrid. Hagrid, being the Keeper of Keys and Grounds at Hogwarts and having a great love for magical creatures, would be interested in what Newt and Harry are up to. They could also meet some of Newt's old friends from his adventures in the Fantastic Beasts series.
In the 'Harry adopted by the Malfoys' fanfiction, one possibility is that Harry would receive a very different kind of magical education. The Malfoys might try to mold him into a Slytherin - like wizard, but Harry's own Gryffindor - like courage would constantly be at odds with that. Also, his relationship with Draco could be very complex, ranging from initial rivalry as they are brought up in the same household to a possible understanding and even friendship later on.
Well, in such a fanfiction, Harry might be given a very different education. The Malfoys could try to indoctrinate him with pure - blood supremacist ideas at first. But as he grows, he might rebel against it. He could also be exposed to a different social circle within the wizarding world. Maybe he would have more interactions with other Slytherin families and this would change how he views things like House rivalries. And his relationship with Dumbledore would be very strained as the Malfoys are not on good terms with Dumbledore.
Definitely Naruto and Grayfia. Naruto is the main protagonist who has his own story and growth arc. Grayfia is the one who changes Naruto's life by adopting him. She could be a noble or a powerful mage. There may be other characters such as servants or comrades of Grayfia who are initially skeptical of Naruto but later come to accept him. And of course, there could be antagonists. Maybe there are some rivals in Grayfia's world who don't like the idea of an outsider like Naruto being in their midst and they try to cause trouble for him.