She could be shocked at first. Just imagine, she thought she knew her family all this time, and then bam, she's adopted. She might be angry too, especially if she feels she's been lied to. But also, she could be curious and eager to find out more about her real family.
Hermione might have a complex range of reactions. Initially, she could be in denial. It's such a big thing to take in. Then, as it sinks in, she might feel a sense of betrayal from her adoptive parents. However, being Hermione, she would also likely see this as an opportunity for discovery. She'd probably start researching in the library about adoption in the wizarding world and look for any clues to her real family's identity. And she might also worry about how her friends, like Harry and Ron, would react to this news.
Hermione's reactions in a fanfiction where she discovers she's adopted could be quite diverse. At the very start, she would most likely be stunned into silence. Her whole world view has been shaken. She may then experience a period of sadness, mourning the family she thought was hers by blood. But her inquisitive nature would soon take over. She'd be determined to find answers. She might question every memory she has of her family life, looking for signs that she was adopted. And she could also become more guarded, worried that others will see her differently now that she knows she's adopted.
She might start to search for her biological parents. This could lead her on an adventure full of mystery and self - discovery. She could use her intelligence and magical skills to track down any clues about her origins.
Discovering she's adopted in a fanfiction could change Hermione in many ways. Firstly, she may feel a sense of loss or confusion about her past. She has always been so confident in her knowledge and self, but this revelation could shake that. She might start to search for her real parents, which could lead her on all sorts of adventures. This could also cause some strain in her relationships with her adoptive parents if she feels they have kept this from her for too long.
In this fanfiction, it could be that Hermione attends a wizarding symposium where the Zabini family is presenting some of their ancient magic. She is initially skeptical but as she listens to their presentation, she becomes intrigued by their knowledge and the way they approach magic. She starts to research more about them on her own, finding out about their famous ancestors and their influence in different areas of the wizarding world. As she delves deeper, she realizes she has a newfound respect and admiration for the Zabini family, thus becoming a fan.
In some fanfictions, Hermione might find out she is a Malfoy due to a spell gone wrong. For example, a spell that was meant to reveal family lineages got mixed up and suddenly she has a connection to the Malfoy family in the magical world created by the fanfiction writer. It could also be a result of a hidden prophecy that links her to the Malfoys in an unexpected way.
She might struggle with her new identity at first. After all, she has always been seen as a Muggle - born. This new discovery could make her question her place in the wizarding world. She may start to explore her pureblood heritage, looking into her family's past and any special magical abilities or traditions that come with it.
One consequence could be that Hermione has to face the Malfoy family. They might try to bring her into their way of life, which she has always opposed. It would be a struggle for her to keep her own values intact while dealing with their pure - blood traditions.
Her relationship with her adoptive parents might become a bit strained at first. She could start to question their motives for not telling her. But over time, she might come to understand their reasons and their love for her remains the same.
Dumbledore's reaction could be complex. He might feel guilty for not realizing it sooner. In some fanfictions, he would try to make amends by providing more support and protection to Harry. Other teachers at Hogwarts, like McGonagall, would be sympathetic and might offer their own forms of help, like extra tutoring or a place for Harry to relax.
One great fanfiction with this theme is 'Hermione's Pureblood Revelation' on FanFiction.net. It delves into how Hermione discovers her pureblood heritage and how it changes her relationships at Hogwarts. She has to deal with the new - found knowledge and the expectations that come with being a pureblood in the wizarding world.
There could also be some unknown characters in the fanfiction. Maybe a secret society within Hogwarts that has been using the cupboard for their own purposes. When Hermione finds out about it, she gets caught up in their affairs. These unknown characters could be students from different houses or even former Hogwarts students who have come back for some hidden agenda related to the cupboard.