Ruby Rose just blasted Katy Perry in a single tweet.

We all love a good celebrity feud and there’s never been one more entertaining – or confusing – than Taylor Swift’s war with Katy Perry.

And now a friend of Swift’s has weighed in, with Australia’s own Ruby Rose criticising Perry in a baffling tweet.

Yesterday Perry dropped Swish Swish – the latest single from her new album – and it seems like Rose is not at all happy about it.

The Orange is the New Black star posted a tweet that’s laced with so much shade and complicated references, you almost need a pop culture dictionary to be able to decipher it.

“Purposeful poop” to “bomb a petit” to a sloppy mess of writing over the top of Funkagenda..stop trying to make ‘Wit..I mean “fetch” happen.

— Ruby Rose (@RubyRose) May 19, 2017

Luckily, we’ve done the hard work for you. So let’s break it down and examine it in all its feud-y goodness.

“Purposeful poop” refers to the “Purposeful Pop”- era Perry tried to start earlier in the year with the release of her single Chained to the Rhythm. Rose very cleverly changed the ‘pop’ to ‘poop’ turning Perry’s own words into the ultimate primary school burn.

We gonna call this era Purposeful Pop. ???? https://t.co/fCllqtlRTm

— KATY PERRY (@katyperry) February 10, 2017

“Bomb a petit” is a reference to Bon Appetit, Perry’s follow up single that kinda, well, bombed on the charts.

When Rose refers to a “sloppy mess of writing over the top of Funkagenda” she’s talking directly about Swish Swish, Perry’s new single which opens with a famous sample of ‘what the f**k’, a track that has previously been used by Funkagenda and Fatboy Slim.

And there’s no points for guessing that “stop trying to make ‘Wit…I mean ‘fetch’ happen” is a reference to Mean Girls. Rose is basically saying that Perry should stop trying to make her new album Witness happen.

Rose then followed up with tweet saying: “I just think with everything going on in the world to go from rebranding as political activist only to ditch it and go low … is … a bummer.”

When Perry’s fans reacted to her tweets, Rose told them they should “buy all her songs so the songs will finally chart”, claiming that if the amount of people who tweeted her had bought Perry’s last three songs “the’d be hits [sic]”.

Perry is yet to respond to the tweet, but we’re pretty sure Rose won’t be invited to sit with her at lunch anytime soon.