A quick sketch
Instead of «Curse-System» there is Police.
When you want to report a griefer you click on a button looking like a police batch.
Then an police officer NPC will appear and ask you «Who do you want to report?».
Then a list appears with all the players on the server.
You can choose the player you want to report.
Then the griefer gets a notification that he got reported to the police.