1x16 - Tale of the Nine Tailed

Ji A is in despair after watching Yeon jumping into the Samdo River to save her. She even goes to visit Taluipa to ask if there’s any way to bring him back. But then, Ji A and Rang get to meet the king of darkness who is one of the afterlife judges. He suggests that Ji A or Rang should sacrifice their life to bring Yeon back to life.