Duff ditches her clean image in an upcoming episode of Community when she plays Meghan - a female who bullies characters on the NBC series.
She told UsMagazine.com: 'I haven't really done anything where I got to be a bitch before.
'It wasn't that I had to do so much preparation, everyone's had someone be mean to them before - but it was just exciting to play something different.'
Although the 23-year-old's character Meghan does meet her match in the character, Abed, played by Danny Pudi.
The newlywed added: '[Meghan acts] super confident but is totally, you know, shallow and scared inside.
'I have this big scene where I walk into the school cafeteria and call [Danny] out and everybody hears and he ends up really embarrassing me and I leave - he comes up with the greatest insults.'