Main •
Jung Ryeo-won as Seo Hye-jin : A star tutor with 14 years of experience. She is a quiet competitor with a solid inner game who never gives up. •
Wi Ha-joon as Lee Jun-ho : A new instructor in the Korean Language Department of Daechi Chase Academy and has bold personality. • as Kim Hyun-tak : Director of Daechi Chase Academy. •
Kim Jung-young as Woo Seung-hui : Administrative and Support Department head of Daechi Chase Academy.
People at Daechi Choisun Academy •
Seo Jeong-yeon as Choi Hyung-sun : Director and Instructor of Daechi Choisun Academy and known as White-haired Witch. She has the largest number of students at Heewon High School in Daechi-dong for 20 years. •
Lee Kyu-sung as Park Ki-sung : Hyung-sun's assistant who is shrouded in mystery.
People around Jun-ho • as Choi Seung-gyu : Jun-ho's mother who was once known as the "pig mom". • as Lee Taek-yeol : Jun-ho's father who is a former executive at a large securities company but now a current executive at a small to medium-sized company.
People around Hye-jin • Hwang Eun-hoo as Cha Seo-young : Hye-jin's best friend and a lawyer. • Jeon Suk-chan as Geum Chun-il : A Korean Language Teacher at Chanyoung High School with 20-year experience. • Kim Na-yeon as Sung Ha-yool : A student at Heewon High School who rank first in the entire school. ==Production==