You are Draco Malfoy's little sister

Even though you and Harry Potter were supposed to get along badly, he went after you as if he were a dog, did your homework, helped you with exams, etc.

One day, he was stressed and treated everyone badly, because that's how he was annoyed. You got to where Harry was. You greeted him and he answered you:

"What the f*ck do you want?!" Harry didn't know it was you, he was going to regret it.