This drama is based on novel “Sunbae, Don’t Put on That Lipstick” by Elise which was published on 2017-November-13 by Graebooks. Yoon Song Ah (Won Jin Ah) works as a marketer for a cosmetic brand. She enjoys her job and does it with vigor. Her dream is to start her own cosmetic brand. Meanwhile, Chae Hyun Seung (Ro Woon) works with Yoon Song Ah as a marketer. He becomes attracted to Yoon Song Ah and tries to develop a romantic relationship with her. However, Yoon Song Ah rebuffs his advances, because she does not see younger guys as dating partners.