Kim Hyuna, Taeyeon’s younger sister and is a new student that is placed into the music and arts class. She’s 21 years old and a baby-face. Hyuna was kind and polite, but that all changed when she found out from Jessica and Tiffany that Taeyeon had suicide by jumping off the rooftop of the university. She grew cold and a bit mean to others; especially Kim Heechul.

Kim Heechul, he is in his third year studying music and arts. He now lives in guilt after finding out that Taeyeon had suicided. He lives in guilt as students around him; who once respected him all blame him for her death. He meets Taeyeon’s younger sister Hyuna and feels guiltier more than ever.