When she skyrocketed to stardom at the tail end of the 2000s, Katy Perry was a girl-next-door gone wild: dancing on tables, kissing cherry-Chapstick-ed strangers, and shooting whipped cream out of her sparkly bustier. Her trademark hits represented pop as pure escapism—fun and frivolous, with production from the era’s biggest hitmakers (Max Martin, Stargate, Dr. Luke). Sixteen years after her breakthrough with 2008’s “I Kissed a Girl,” the era from which Perry emerged has cycled back into fashion as a nostalgic trend. But on her sixth album (not including her contemporary Christian record as Katy Hudson), named for her angel number—and for how people typed “I love you” back in the pager era—the 39-year-old singer is focused on the present.