Did Katy Perry just reveal that she is Taylor's Swift's celebrity "enemy?" It sure seems like it.

The "Dark Horse" singer tweeted a message that seemed to suggest just that hours after Taylor Swift informed the world, via her Rolling Stone cover story, that she recently wrote a song about her feud with another famous songstress.

But if the "bad blood" between Swift and Perry is true, could John Mayer have played a factor?

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

— KATY PERRY (@katyperry) September 9, 2014

Perry's "Mean Girls" reference appeared on her Twitter page just one day after Swift's Rolling Stone magazine cover story was released.

In the interview, Swift revealed that her upcoming album, "1989," will include a song that she wrote about a famous female singer who allegedly has had it out for Swift over the last few years. The track, titled "Bad Blood," leaves the star unnamed but calls her out for trying to mess with Swift's business affairs.

"She did something so horrible 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 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."

Swift confessed that "Bad Blood" was written as payback for the anonymous enemy's misdeeds.

"I would just be constantly writing all these zingers - like, 'Burn. That would really get her," Swift told Rolling Stone.

But could Swift's song and the feud really have to do with John Mayer, who dated both of the pop divas?

Swift had a secret fling with Mayer that ended in 2010. Perry then publicly dated Mayer on and off for two years. The couple even recorded a duet together called "Who You Love" and filmed the music video before breaking up in 2014.

While Swift maintains that her celebrity feud was primarily a professional issue, she did admit that personal matters were involved as well.

"But I don't think there would be any personal problem if she weren't competitive," said Swift.

So, could it be time to declare Team Swift or Team Perry? While neither has confirmed the feud, one thing's for sure. Fans of both ladies will definitely be waiting to hear what tidbits "Bad Blood" has to spill.