Delancy maybe cruel to everyone in princess charm school. But she can always change and become a kind Delancy. Like what happened at the end of the movie. When she figured out that Blair was the true heir to the throne, she realized how selfish she was to Blair. And she felt guilty of stealing Blair's throne. She did everything to return the Gardenia's rightful heir because she knew that she was doing the right thing.So it means Delancy is not very cruel. She just want to prove to everyone that she is better than anyone but she was wrong. Delancy is not anymore cruel. She is now a sweet and kind Delancy.