After Harry saves Hermione, their relationship could evolve in a more complex way. There could be a newfound respect between them. Harry might have a sense of pride in being able to protect her, and Hermione may feel a bit more vulnerable around him. This could lead to some awkwardness at first, but as they work through it, they become closer. They might start spending more time together, not just for school or magic - related things, but also just to be in each other's company. Their friendship could become the cornerstone of their lives, with Harry always being there to protect Hermione and Hermione always being there to support Harry with her knowledge and wisdom.
Maybe Viktor has been cursed in some way in the fanfiction, and his actions towards Hermione are involuntary. Harry, being observant, picks up on the strange behavior. He may call upon his friends for help, like Ron. Together, they could form a plan. Harry might use his invisibility cloak to get close to Viktor and Hermione without being noticed and then use a powerful stupefy spell to stop Viktor before he can harm Hermione. And then they would figure out how to break the curse on Viktor.
In fanfiction, the scenario of Draco saving Hermione from Viktor can be quite complex. It might be part of a larger plot where Draco is secretly working against some dark forces that Viktor has unknowingly become involved with. Hermione could be a key target, and Draco, having some inside information, decides to protect her. This could lead to a whole new relationship dynamic between Draco and Hermione, as she now sees him in a different light, and Draco starts to question his own allegiances.
Perhaps Viktor was jealous of Ron and Hermione's relationship. In the heat of that jealousy, he might have overstepped boundaries and put Hermione in a threatening situation. Ron, being protective, wouldn't stand for it and thus saved her. For example, Viktor could have tried to force Hermione to go somewhere with him against her will.
In the fan fiction, Viktor might use his excellent swimming skills. He is from Durmstrang after all, which is by the Black Lake. He could have swum quickly to Harry when he was in trouble in the water, grabbed him, and swam back 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.
One possible scenario could be that in this fanfiction, Harry discovers that Hermione is being bullied by some dark - minded students at Hogwarts. He steps in immediately, using his skills and the respect he has among his peers to put an end to it. Maybe he threatens the bullies with exposure to the professors if they don't stop.
If Hermione realizes her mistake and tries to make amends, it could lead to a deeper understanding between them. They might have to work through their feelings and have some difficult conversations. For instance, Hermione might have to explain her reasons fully, and Harry would have to decide if he can forgive her.
In the fanfiction, Draco could be an observer. He might not directly interfere with Hermione and Viktor's relationship but instead watch from afar. He could be in a state of self - reflection, comparing their relationship to his own past relationships or his family's view on love and marriage. As he observes, he might learn something about himself and his own capacity for love, and this could lead to his own character growth without directly involving himself in Hermione and Viktor's engagement.
Well, he could use his magic skills. Maybe he casts a powerful spell on Ron to stop him and then takes Hermione to a safe place, like Hogwarts where there are protective enchantments.
Maybe Harry uses his magic skills to immobilize Ron. He could cast a spell like 'Petrificus Totalus' on Ron right when he's about to attack Hermione, thus stopping the beating.