'KUWTK': Kim and Khloe Kardashian Confront the Person Behind 'Nori's Black Book'
, and Kim and Khloe Kardashian are determined to solve one of their family's biggest mysteries!On Thursday's new episode of the hit reality series, the sisters did some sleuthing to track down the person behind the hilarious Nori's Black Book Instagram account, a social media satirization of the family through the eyes of Kim and Kanye's eldest daughter, North West.At first, Kim and Khloe are convinced that the person behind Nori is someone in their inner circle — citing her spot-on details about the family's personalities — and they grill celebrity hairstylist and family friend Jen Atkin and Kim's former assistant, Stephanie Shepard, who both deny being the Nori mastermind.Finally, Kim puts Tracy Romulus, Chief Marketing Officer for KKW