Hermione is known for her preparation. In this fanfiction, she might have come across some rare magical artifacts. One of these artifacts could have the ability to nullify the effects of the veil. She had it on her when Sirius was in danger. She quickly activates the artifact, creating a protective field around Sirius and herself. This field repels the veil's power and allows her to pull Sirius to safety. Also, her friendship with Sirius might have given her an extra boost of determination. She refused to let him go and this strong will, combined with her magical resources, made it possible to save him.
In some versions, Hermione might use her advanced magic knowledge. She could have discovered a spell that counteracts the pull of the veil. Maybe she found a way to disrupt the dark magic associated with it and was able to pull Sirius back from the brink just in time.
Well, it could be that Hermione has been researching about the veil in secret. She might have found an ancient charm or incantation that gives her the power to reach into the veil without being affected herself. And with her quick thinking and powerful magic, she grabs Sirius and yanks him out. Another possibility is that she uses some sort of time - turning device to go back a few seconds before Sirius is fully pulled in and then is able to stop it from happening at all.
In many such fanfictions, Sirius might use his magic skills. He could be quicker and more powerful than Lucius in a duel. Maybe he uses a powerful spell to stun Lucius and then whisks Draco away to safety.
Well, in many such fanfictions, Harry might use his magic skills. He could cast a powerful stupefy spell on the troll to stop it in its tracks and then quickly lead Hermione to safety. Maybe he also uses his quick thinking and knowledge of the Hogwarts corridors to find a hiding place where the troll can't reach them.
Well, perhaps he uses his influence in the wizarding world. Maybe he has some connections or knowledge that allows him to intervene and get Hermione out of the abusive situation. For example, he could use his status among the pure - blood families to put pressure on the abusers.
Well, in some versions, Fred might use his quick-witted magic skills. He could cast a distraction spell to draw Bellatrix's attention away from Hermione. Maybe a spell that creates multiple illusions of himself, confusing Bellatrix long enough for him to grab Hermione and disapparate them to safety.
Well, in some versions, Ron might use his quick wit and knowledge of Hogwarts' secret passages to outmaneuver Draco. He could lead Hermione to safety through a passage that Draco doesn't know about.
Often, it begins with Hermione trying to help Sirius deal with his post - Azkaban trauma. She uses her knowledge and compassion to reach out to him. As he heals, he starts to see her in a new light. Their relationship then grows as they start to understand each other better. The lemon parts usually are used to explore their more passionate and private moments, which are often written in a very tender and intense way, adding a new dimension to their relationship.
Well, perhaps Snape uses his position as a teacher to step in. He could have been observing the situation secretly and when Draco was about to do something harmful to Hermione, Snape intervened with a firm command or some magic spell to stop Draco in his tracks.
Well, it could be that Lucius uses his powerful influence in the wizarding world. Maybe he intimidates Ron with threats related to his family's status or he uses some dark magic to create a distraction and whisk Hermione away.
Well, it could be that Snape has been secretly observing Ron's erratic behavior towards Hermione. When the situation gets out of hand, he intervenes. He might use his position as a teacher to discipline Ron and in the process, saves Hermione. Snape is a complex character with a lot of power and knowledge, so he could use various means like his occlumency skills to sense the danger Hermione is in and act accordingly.
He might use his magic skills to create a protective shield around Hermione when Sirius approaches with a menacing look. For example, he could quickly cast a spell like 'Protego Maxima' to keep her safe.