In our September cover story, Taylor Swift explained the inspiration behind her then-unheard song "Bad Blood," telling Rolling Stone that an unnamed female artist had crossed her one too many times. "For years, I was never sure if we were friends or not," she said. "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?'" Swift went on to hint at a business-related dust-up that led her to believe "we're just straight-up enemies." When the article hit stands, speculation swirled and eventually landed on one Miss Katy Perry, who wasted no time in tweeting, "Watch out for the Regina George in sheep's clothing." The Mean Girls-themed mixed metaphor seemed pretty blatantly about Swift, and gossip sites quickly pointed to an incident in which three of Perry's backup dancers for the California Dreams 2011 tour were given spots on Swift's Red tour after Perry's had ended. While out with Swift, Perry's people allegedly reached out to the dancers asking if they'd want to return for the star's upcoming Prism tour, which would require them to leave Swift's early. The dancers ended up defecting to Perry, Swift unfollowed them on Twitter (these are things that Taylor Swift fans notice) and a once-seemingly-cordial relationship between the two biggest pop stars in the world apparently turned ugly fast.