A possible plot is that she gets into trouble when some dark wizards mistake her for a key to some powerful dark magic related to Harry and Sirius. So she has to rely on her friends and her own wits to escape and prove that she's not what they think. Also, she could be involved in a time - traveling adventure, where she meets her father and godfather at different points in their lives, which gives her a new perspective on their relationships and her own identity.
She might find herself in the middle of a mystery regarding a lost magical artifact that was once important to Harry and Sirius. As she tries to solve this mystery, she uncovers long - forgotten family secrets. This could lead to her having to make difficult choices about loyalty and what it means to be part of her family. Along the way, she forms new alliances with other young witches and wizards who help her in her quest.
Perhaps Sirius Black's daughter has a special connection to Harry through a long - forgotten prophecy. They start to notice strange coincidences and shared dreams. As they investigate, they find out that their destinies are intertwined in a way that could change the wizarding world. It could involve a journey to find a lost magical artifact that holds the key to fulfilling the prophecy.
She could be a brilliant potion - maker, which is highly valued in Slytherin. Her story could revolve around her trying to create a new potion that has something to do with her father's legacy. Or perhaps she gets involved in a competition within Slytherin to prove herself worthy, all while dealing with the shadow of her father being a member of the rival house.
A possible plot is that Hermione discovers some long - lost secrets about her father, Sirius. This could lead her on a quest to uncover the truth about his past and his family. Along the way, she might find out about some hidden magical artifacts or spells that were associated with Sirius's family line. It could also involve her interacting with Sirius's old friends and enemies, which would create a lot of interesting dynamics. For instance, she might have to deal with some who are still bitter about Sirius or others who want to protect his legacy through her.
One plot idea could be Hermione discovering her true parentage through a series of magical events. Maybe she stumbles upon an old family heirloom that has a connection to Sirius. Another could be her having to deal with the reactions of her friends, like Harry and Ron, who are shocked by this revelation. She might also face challenges within the wizarding community as Sirius had a somewhat controversial past.
One idea could be that the daughter inherits Hermione's intelligence and Sirius's rebellious spirit. She might use her smarts to uncover secrets about the wizarding world that were long buried, like hidden spells or lost histories. Another plot could involve her struggling to fit in at Hogwarts, being the daughter of two such well - known figures. She could face both envy and admiration from her peers.
One plot idea could be Sirius escaping Azkaban earlier and secretly taking care of baby Harry. He could teach Harry magic in hiding, away from the Dursleys. Another could be Sirius using his animagus form to be close to baby Harry without being detected, like a secret guardian watching over him at all times.
One idea could be that she discovers her true identity while attending Hogwarts. Maybe she has some unique magical abilities that are related to her Black heritage. Another plot could involve her search for her father's friends, like the Marauders, to learn more about him.
In a fanfiction plot, Harry might teleport to Sirius in the middle of a battle. Sirius is surprised but quickly realizes they can turn the tide of the battle together. They start using their combined skills and knowledge. Harry could learn some advanced defensive magic from Sirius during this time. And as they fight side by side, their bond grows stronger, which has a significant impact on Harry's development as a wizard and his understanding of his family.
One possible plot idea could be that Sirius catches Harry and Hermione in the middle of a secret plan to save a fellow student from a dark magic threat. Sirius, initially thinking they're up to something dangerous, then realizes their noble intentions and decides to help them. Another idea is that Sirius catches them while they are exploring a hidden part of Hogwarts that is related to an old mystery about his family. He then shares his knowledge about it with them, leading to an exciting adventure.
One idea could be Sirius teaching Harry all the secret passages around Hogwarts that he knew as a student. Another could be Sirius introducing Harry to the wizarding world's underground music scene. Or perhaps Sirius helping Harry deal with his nightmares about Voldemort by sharing his own experiences of facing dark magic.