His character could develop in a more complex way. Binding the succubus might force him to confront his own desires and weaknesses. He may become more empathetic as he tries to understand the succubus, who might not be all bad. At the same time, he would have to be stronger in his willpower to resist her charm, which could lead to a toughening of his character.
Harry's character could become more cautious. Dealing with a succubus would make him realize that there are many dangerous and unpredictable forces in the magical world. He might also become more secretive as he doesn't want others to know about the succubus he has bound.
One possible plot could be that Harry, perhaps in a search for power or knowledge, binds the succubus. But then he has to constantly battle her wiles and temptations as she tries to break free. He might use magic he's learned at Hogwarts to keep her in check.
Harry could develop a darker side to his character. Since the succubus has her own set of moral and ethical values which are different from the typical wizarding world's, Harry might be more accepting of morally grey areas in magic. For instance, he might be more willing to use curses that are considered unethical in the normal wizarding world. However, he could also have a strong sense of loyalty to the succubus, seeing her as his true family.
Well, it could be that Harry, in this fanfic, discovers a way to bind the succubus familiar through some ancient magic he stumbles upon. Maybe he needs its powers for a particular task, like fighting a new dark force in the wizarding world.
Maybe there's a demon lord who has some sort of claim over the succubus. This demon lord sees Harry's binding of the succubus as an insult and a threat, and thus becomes the main antagonist. He would then send his minions or use dark magic to try and break the bond between Harry and the succubus.
If Harry became a succubus, his magical abilities would transform. He could gain the ability to influence others' emotions on a deeper level. His personality might become more complex as he tries to balance his old self with the new instincts of a succubus. He may also become more isolated as some in the wizarding world might fear or misunderstand his new form. But at the same time, he could also find new friends who are more accepting of his unique situation.
Harry would likely become more cunning. He has to survive in Voldemort's lair, so he'd learn to hide his true feelings and intentions. For example, he might pretend to be more submissive than he really is to gain Voldemort's trust slightly.
Harry might be more self - assured. Since his grandparents are likely to be more loving and supportive than the Dursleys, he would grow up with a better sense of self - worth. He could be more open - minded as well, because his grandparents' different parenting style would expose him to different ideas and ways of thinking.
Harry would develop a stronger sense of intellectual curiosity. He'd be constantly seeking knowledge, not just about Voldemort but about all aspects of magic. He might even start his own study groups in Ravenclaw. His friends would also be those who share his thirst for knowledge, which would further fuel his development. He'd probably become more of an academic star, impressing professors with his well - thought - out answers and research.
His character would become more reserved perhaps. Sesshomaru is not very expressive, and Harry might pick up on that. He would also be more self - sufficient and less likely to rely on others easily.
Harry would likely be more confident in his Quidditch abilities right from the start. Since Krum is a Quidditch hero, he would train Harry well. So, Harry might be more cocky on the Quidditch pitch compared to the original story.