The relationship between pop star and stylist is a dance between muse and artist — and, just like Julia Fox, we don’t say “muse” lightly. Take, for instance, Lady Gaga and Nicola Formichetti, or Charli XCX and Chris Horan, or Dara and Addison Rae. A stylist and image maker who’s most recently caught our attention is Ron Hartleben, the man behind Sabrina Carpenter’s “Please Please Please” furs and corsets and Tyla’s notably excellent fashion run of late. Making your favorite main characters look good goes beyond having good taste, as Hartleben tells NYLON. “It's about confidence and comfort,” he says, “because if they don't believe in what they're wearing, then no one else will.” After cutting his teeth under Carine Roitfeld at CR Fashion Book, Hartleben has worked in editorial and celebrity styling,...