Taylor Swift fans don't hold back shade on Katy Perry and Calvin Harris collaboration

Things got extra shady on Twitter on Tuesday when Calvin Harris teased the list of upcoming collaborators from his new album. 

In a video posted on Twitter, the music producer teased his album, Funk Wav Bounces Vol. 1

The list of featured artists includes Nicki Minaj, Ariana Grande, Snoop Dogg, Frank Ocean and, yes, Katy Perry. 

For those blissfully unaware of why this is a big deal, Harris used to date  Perry's frenemy Taylor Swift. 

Well, Swift's fans — who are called Swifties — took notice of this impending collaboration and felt very strongly about Perry teaming up with Swift's former boyfriend. 

According to a flurry of tweets, the Swifties found it shady that Perry and Harris were working together. They predict this collaboration will flop and that Swift will come out on top:

While Swift's fans were having a meltdown over the collaboration, others were living for the pettiness of Perry and Harris teaming up:

Your move, Taylor. 

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