Demi Lovato blew us away with her performance at the 2015 MTV VMAs, but comedian Kathy Griffin wasn't impressed with her rendition of "Cool for the Summer" — and the pop star fired back.

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It all started when the host said that Demi's show was "very obviously live," implying that it was not a good performance.

Well, the pop star responded, LOL-ing over the fact that Kathy is still following her career. (They got into a heated Twitter feud last year.)

The comedian followed back with a throwback photo of them together.