One possible reason could be miscommunication. Maybe Ginny did something without fully explaining her intentions to Harry, and in the heat of the moment, he yells. For example, if she made a decision about their relationship without consulting him first.
She might get angry right back. Ginny is a strong - willed character. So, if Harry yells at her unjustly, she could stand her ground and yell back, not willing to be pushed around.
In a fanfiction, it could be that Ginny is being too reckless. Hermione, being the more cautious one, is always worried about getting into trouble. If Ginny is constantly sneaking out or getting involved in dangerous adventures, Hermione might yell at her to stop putting herself and others at risk.
One possible reason could be jealousy. Maybe Ginny is jealous of Hermione's close friendship with Harry or her academic achievements. In the wizarding world, relationships can be complex, and Ginny might feel overshadowed by Hermione at times.
It could strain their friendship. Yelling is not a positive form of communication, and it might make Ginny feel attacked. She could become defensive and start avoiding Hermione. On the other hand, if Ginny understands Hermione's reasons, it could lead to a deeper conversation and actually strengthen their bond. For example, if Hermione yells because she's worried about Ginny's safety, Ginny might realize how much Hermione cares.
On the other hand, it could also be a turning point for the better. If they talk about what led to the yelling, they might clear up misunderstandings and become closer. For example, if Ginny was yelling out of fear for Hermione's safety in a dangerous situation, Hermione might realize Ginny cares deeply for her.
Harry might become more determined to prove Snape wrong. He's a stubborn character, and Snape's yelling could fuel his desire to show that he's not the misbehaving student Snape seems to think he is.
Maybe she's yelling at Ron. Their relationship in fanfictions can be quite complex. If Ron says something insensitive or does something stupid, like forgetting an important task that could put their mission in jeopardy, Hermione would surely yell at him.
Perhaps in a 'harry potter yells fanfiction', Harry yells when he discovers that someone has been spreading false rumors about his friends. He could be in the Great Hall, stand up, and yell at the perpetrator, creating a big scene full of drama and conflict within Hogwarts.
The Weasley twins could be part of it too. Suppose Harry yells in excitement or anger about a new prank idea that the twins have come up with that might be a bit too dangerous. They could either encourage his yelling or try to tone it down, depending on their mood. And Malfoy might overhear Harry's yell and use it as an opportunity to taunt him, adding more conflict to the fanfiction.