Must You Go? Episode 4

Back in Joseon, Yeun had promised Yu Jeong that he would always be by her side no matter what happens. However, the last thing he remembers of Joseon is the fact that he had to watch her burn in a fire. When Lee Won knocks on Yu Jeong’s door on the day of the audition, Yu Jeong hides Yeun and leaves. When he comes out from hiding, Yeun realizes that Yu Jeong has disappeared. (Source: Viu)