Hermione would likely be a mix of disappointed and worried. Disappointed because Harry is usually responsible, and worried because she cares about him. So she'd probably try to figure out why he got drunk in the first place.
In this fanfiction situation, Hermione's reaction could be quite complex. At first, she may be shocked and angry that Harry has let himself get into such a state. But then, her natural caring side would take over. She'd likely stay by his side, making sure he's okay. She might also start thinking about what has been bothering Harry so much that he resorted to getting drunk, and she could be determined to help him through whatever it is, whether it's problems with school, his past traumas, or his relationships with others.
Often, Harry will offer her a handkerchief or a tissue if there is one available. He might also put his arm around her in a comforting gesture. In 'The Common Room Crisis' fanfic, he does just that and then stays with her, listening intently as she pours out her feelings. He is patient and understanding, which is in line with his character in the original books. He tries to make her laugh or at least smile by sharing a joke or a funny memory. This shows his deep friendship and care for Hermione.
In such a fanfiction, Hermione might first be shocked to see Harry in that state. She could scold him gently for getting drunk, as she is usually the more level - headed one. Then, she would probably try to sober him up, perhaps using a spell or getting him some water and food.
Snape would likely be shocked and then enraged. Harry is supposed to be the hero of the wizarding world, and seeing him drunk would be a huge disappointment. He would most likely drag Harry to his office, lecture him about propriety and the expectations placed on him as a wizard, and probably assign some form of punishment like a long detention. But as he observes Harry more closely during this time, he might start to wonder what drove Harry to this and if there are deeper issues that need to be addressed.
She probably comforts him right away. Hermione is a very empathetic person. She might give him a big hug and let him cry on her shoulder.
She might be initially shocked. After all, Draco is usually seen as this tough Slytherin. But then she could feel sympathy. For instance, she might offer him a handkerchief without saying much at first.
She could also try to reason with the Death Eater. Hermione is known for her intelligence and ability to think on her feet. She might try to appeal to any sense of humanity the Death Eater might have, reminding him of the consequences of following Voldemort's evil path.
He might be initially shocked. After all, he has always seen Hermione as a friend, and suddenly finding out she's his twin would turn his world upside down. He could feel a mix of confusion, excitement, and also a bit of unease as he tries to understand how this could be possible and what it means for their relationship and his own identity.
Hermione is likely to be furious. She might confront Harry immediately, demanding an explanation. Given her strong sense of right and wrong, she would not let this slide easily. She could also stop sharing her work with him in the future.
There might be some fanfiction out there that involves this scenario in a non - inappropriate way. However, it's important to look in proper fanfiction platforms like Archive of Our Own. They have strict content policies to ensure that any such stories are more about the characters' relationship development or some interesting plot twists rather than anything improper.
Harry could initially be in shock. He's always counted on Hermione, so her abandonment would be a huge blow. He might feel a sense of betrayal and confusion.