Hermione's friends would likely be very excited. They might plan some special activities for her parents. For instance, they could arrange a little tour of the Forbidden Forest (from a safe distance, of course). They would also share stories about Hermione at Hogwarts, how smart she is and all the adventures they've had together. And they would be happy to answer any questions Hermione's parents had about the wizarding world.
At first, some of Hermione's friends might be a bit shy. But then they would see how friendly and interested Hermione's parents are. Harry would probably tell them about how Hermione has saved their lives on multiple occasions. Ron would joke around with them and offer to take them to the Gryffindor common room. All in all, they would make her parents feel welcome and part of the Hogwarts family.
In fanfiction, Hermione's parents might be amazed by the magic all around. They could be shown the Great Hall and be astounded by the floating candles. Maybe they get to meet some of Hermione's friends like Harry and Ron, and have a friendly chat with Dumbledore who would explain the magical world to them.
She would be devastated. Hermione is a very emotional person deep down. She might isolate herself at first, not wanting to talk to anyone, even her closest friends like Harry and Ron. She'll probably go through a phase of denial, not believing that her parents are really gone.
Harry would probably be very supportive. He knows what it's like to grow up without parents, and he would see Hermione's decision as a very kind and noble one. He might offer to help in any way he can, like teaching the child some of his own skills in magic or defense against the dark arts.
Harry would likely be furious. He'd immediately start planning to rescue Hermione. He might try to gather evidence of the dark magic used to enslave her and take it to the teachers. Ron, on the other hand, would be impulsive. He'd probably want to storm into the Slytherin common room right away to free Hermione, without much of a plan.
She would probably be in awe. After all, she has heard so much about them from Harry. She might be a bit nervous at first but would quickly warm up and start asking them all sorts of questions about their lives and magic.
The teachers would probably be in a bit of a panic at first. They'd need to make sure Hermione and the baby were okay. Professor McGonagall would likely take charge, ensuring that proper medical care was provided and that the students were kept away from the area to give Hermione some privacy.
Harry would probably be initially cautious. He has a long - standing feud with the Malfoys. But knowing Hermione, he would gradually come around and support her. He might even see it as a chance to break the cycle of hatred between the families. Ron, on the other hand, would be more vocal in his doubts. He would question Hermione's decision, but in the end, he would also be there for her, especially if he saw how much the baby needed care.
They could have been put under some sort of spell by the Order to forget about Hermione. In that case, they would have just gone on with their lives, completely unaware that their daughter had been taken. However, if the spell was not perfect, they might have had some strange feelings or dreams about a missing child.
Harry and Ron would likely be very shocked and concerned. They know Fenrir is a dangerous werewolf, and they might not understand how Hermione got into this situation. They would probably try to persuade Hermione to leave Fenrir at first.
Hermione's friends from Hogwarts like Harry and Ron might be a bit shocked at first. Ron, in particular, might have some mixed feelings as he has had a bit of a competitive streak with Viktor in the past. But eventually, they would come around and support her. Viktor's friends from Durmstrang would probably be more accepting as they might respect his choice more blindly. They could be excited for him and offer their own unique magical gifts or knowledge for the upcoming baby.