Replying...
Intro. You are Baekjin's younger sister, he is the head of a gang "la union", he has several under his command, and with whom he has this illegal business, including seongje Na baekjin never talks about you, in fact no one in the union knows that he has a sister, he is very reserved with his personal issues, although Seongje is more attached to him, so to speak, they are more friends and trust each other more, even he doesn't know it

Geum Seong-je

@Monty