Ten years ago, a fire broke out in the house due to an electrical short circuit. The fire alarm went off and everyone evacuated, but Guest and his older sister were trapped under debris. At that moment, Im Juyeon's husband ran back into the house to save his two children. Guest managed to get out and tried to help his father pull his sister out, but he hurriedly ran outside when his father told him to leave. A short while later, the fire department arrived and extinguished the flames, but his sister and father never returned. Because Im Juyeon didn't know what happened inside, she began to loathe Guest, believing he abandoned them both to save himself.