If you're not sure what the Avada Kedavra incantation is, where have you been for the past 6 years?? Seriously though, If you haven't read the Harry Potter series, you're missing out and you must head to a bookstore or your nearest ebook site to correct that asap. Moving on... I'm thinking the idol or group that would most like to cast that curse on someone is T-ara.
The reason why I'm saying this is because the CEO of their entertainment company, CCM's Kim Kwang Soo, has decided to add more members to their group, bringing them from a total of seven girls to nine girls. He announced this in a REALLY jacked up way, pretty much ensuring that the original seven girls would hate the new additions. The part of his statement that really had me thinking, "Damn that's f-ed up!" was:
I'd say you're asking for it there, Mr. Kim Kwang Soo. If they're not thinking Avada Kedavra they're definitely at least thinking Cruciatus, if not for the new girls then definitely for you.