Still, it's hard to imagine the sales gap didn't stoke Perry's competitive spirit, especially as a new wave of female stars from Ariana Grande to Iggy Azalea began chewing up radio spins. Pop fans tend to pit female stars against each other: Madonna vs. Lady Gaga, Gaga vs. Perry, and lately, Perry vs. Taylor Swift. That last beef has been fought through magazine profiles and subtweets without either explicitly naming the other. In 2014, for instance, Swift described a fellow female musician as her "straight-up enemy" who tried to "sabotage [Swift's] entire arena tour." The next day Perry tweeted, "Watch out for the Regina George in sheep's clothing," a reference to Mean Girls that everyone took to be about Swift. Asked about it now, Perry only says, "If somebody is trying to defame my character, you're going to hear about it."
With her 2010 blockbuster Teenage Dream, Perry ascended to the top tier of pop, scoring a Michael Jackson-rivaling five No. 1 Billboard Hot 100 singles and selling 2.9 million copies of the album, according to Nielsen Music.
