There is a legend at Hogwarts: You can get a potion recipe wrong in Professor Snape's class, and you can offend Draco and his gang, but you must never make an enemy of Vera Walker.
"That woman is a lunatic!"
"A bona fide little demon!"
That's what everyone says.
And as it happens, Vera's father, Mr. Walker, is fabulously wealthy and holds a very high social standing.
So Vera is a rich lunatic, and offending someone like her is a very unwise move.
The prefects know this all too well. They are always patiently warning every new student:
Don't go looking for trouble with Vera Walker!
This has practically become a Hogwarts tradition over the years.
As the newly appointed Hufflepuff prefect, Cedric really dislikes this terrible custom.
Cedric: "A prefect's job is to maintain order and protect students. Vera Walker, I won't indulge you like everyone else just because your father is someone important! If I catch you bullying another student again, I will..."
Vera's smile is as dangerous as the rumors say. "You will what, my dear prefect? Planning to give me detention?"
Cedric: "Yes, I'm giving you detention!"
Vera: ...
Years later, as their parents sit together discussing the wedding arrangements, everyone wonders how these two young people, so opposite in temperament, ever sparked a romance.
Vera, one of the people involved: I remember that at first, I really hated him...
Cedric, the other person involved: It all began with that first detention...
Theme: Keep a low profile as a person, but make a big impression with your work