In a fanfiction, it might happen when Ron has finally mastered a difficult spell. Hermione is so proud of him that she can't help but kiss him on the cheek. It could also be that they are on a trip outside of Hogwarts, and Ron has been really helpful and protective. So, Hermione kisses him on the cheek as a sign of her affection and thankfulness. Maybe it's during a time when Ron is feeling down about himself, and Hermione's kiss on the cheek is her way of cheering him up and showing that she believes in him.
A possible scenario is that they are working on a secret project together. When they finally achieve a major breakthrough, Hermione is so excited that she kisses Ron on the cheek. It could also occur at a Hogwarts ball. Ron looks really dashing in his robes, and Hermione, a bit flustered by his appearance, gives him a kiss on the cheek. Or, in a moment of reconciliation after an argument, Hermione kisses Ron on the cheek to show that she has forgiven him and that their friendship is still strong.
Well, it could have a big impact. For Ron, it might be a moment of validation. He may have been longing for some sign of Hermione's affection. This kiss could make him more protective of her. For Hermione, it might be a spontaneous act of affection that she didn't really think through. But it could start a chain of events where they both become more aware of their mutual attraction. It could also cause some jealousy among other characters who might have feelings for either Ron or Hermione, which in turn could add some drama to the fanfiction.
It could be that Ron starts dating another girl in the fanfiction, and Hermione has feelings for him. Seeing him with someone else would be heart - breaking for her and cause her to cry.
One possible scenario could be that Ron is extremely nervous when he asks Hermione. He might stutter and fumble over his words, making Hermione initially think he's joking. But then he manages to get out a sincere invitation, and Hermione is pleasantly surprised.
One possible scenario could be that Ron says something really mean to Hermione during an argument, and Draco, who has secretly been observing Hermione's intelligence and kindness, steps in to defend her. Maybe he uses his quick wit to shut Ron down verbally.
One possible scenario could be that in the fanfiction, Harry shows a deeper understanding of Hermione's goals and dreams. For example, he might support her in her academic pursuits more wholeheartedly than Ron. Maybe Harry is more involved in her fight for the rights of house - elves or other causes she cares about.
One possible scenario could be that after the battle, Ron and Hermione are both in a state of relief and joy. They look at each other, and without a word, Ron just leans in and kisses Hermione. It's a moment of pure emotion, a celebration of their survival and their unspoken feelings for each other.
Typically, it focuses on the emotional build - up to the kiss. It might show their arguments and reconciliations before finally getting to that romantic moment.
Perhaps Hermione confronts Ron about his lack of commitment to their friendship or to their studies. In the fanfiction, she might be tired of always having to push him to do better and finally snaps at him. For example, she could bring up all the times he's slacked off during group projects or when they were preparing for exams.
There could be a break in their friendship. Ron might realize he made a mistake, but Hermione might not be so quick to forgive. It could take a long time for them to get back to the way they were, if they ever do. They might have to go through a lot of awkward moments and difficult conversations.
One possible scenario could be after a big argument and making up. Maybe they had a fight over something silly, like Ron being jealous of Hermione spending too much time with a new wizard at Hogwarts. Then, after realizing their mistake, they have a heartfelt moment and share their second kiss.