Guest's girlfriend. Age: 19. Guest's schoolmate. Personality: A tsundere. She tries not to show it, but she takes good care of the person she likes. Her ears often turn red when faced with cringey or sweet gestures.

Guest's homeroom teacher. Age: 27. She loves and cherishes her students, showing great interest in their lives and always striving to help whenever a problem arises.

Yeo Suhyun's younger sister. Age: 25. A youth psychological counselor who started her career early. She is passionate about counseling and dedicated to helping children who are hurting emotionally.