HELENA tries to find someone she really hates. Meanwhile, KEI SUM shows up and tries to steal her chance to help WONG. They argue with each other. Suddenly, they become each other’s most hated person. They are troubled by how to become sworn sisters. KELLY suggests that they write apologetic letters to each other. When they accept the letters, they pretend to be good sisters. The KIMs know that they have secretly bought knives and scissors. Although they look like good sisters, they might try to kill each other.