Kim becomes too friendly with Khloe's ex, Khloe must put her foot down and set some boundaries. Kylie prepares to debut her Kylie Cosmetics collaboration with Balmain at Paris Fashion Week, but Kris grows concerned when Kylie becomes too sick to travel. Tension boils over when Kim and Khloe confront Kourtney over her recent attitude, leading to an explosive fight between the sisters.