Hard to believe that Taylor Swift would write a song about someone she doesn’t like right? Well According to Taylor, there is only one song on her 1989 album that she feels is angry. The track is titled Bad Blood and according to Page Six, it is about Katy Perry.

Taylor didn’t come out and admit that she was talking about Perry or any other artist in the song, but it does seem like Perry is who she is referring too.

“For years, I was never sure if we were friends or not,” she said during an interview with Rolling Stone. “She would come up to me at awards shows and say something and walk away, and I would think, ‘Are we friends, or did she just give me the harshest insult of my life?'”

Then last year, the other star crossed a line. “She did something so horrible,” Swift said. “I was like, ‘Oh, we’re just straight-up enemies.’ And it wasn’t even about a guy! It had to do with business. She basically tried to sabotage an entire arena tour. She tried to hire a bunch of people out from under me. And I’m surprisingly non-confrontational – you would not believe how much I hate conflict. So now I have to avoid her. It’s awkward, and I don’t like it.”

You can read our full Taylor Swift cover story right now: http://t.co/pjy56VeqzD http://t.co/9deopoA9pv

— Rolling Stone (@RollingStone) September 8, 2014

While Taylor insists that the bad blood wasn’t caused by a boy, Perry and Swift do have an ex in common and seem to have butted heads over him before. A few years ago Taylor was dating John Mayer and after they broke up Katy accused Taylor of using his fame to gain sympathy for herself and an audience for her music.

Taylor did write her song Dear John about Mayer and also openly talked about him in interviews. Katy dated Mayer a short time after Taylor and didn’t appreciate her remarks or the song.

Only Taylor knows for sure who the song is about, but it seems like Perry may think it’s about her as well. She recently posted a tweet that seems to apply to the song and Taylor’s recent interview response.

Watch out for the Regina George in sheep's clothing…

— KATY PERRY (@katyperry) September 9, 2014