lol idk why i assumed they were asking about Jiwoo (got only Jiwoo on the brain i guess (≧∀≦)
but (i donno, maybe am assuming again or maybe it was actually something i assumed after reading a chapter - which i don't recall 100% as it's been ages since i started this) BUT i came to the conclusion that she was in her early 20's, cause of her younger brother (& as she is the head of their organization for a few yrs), what she took over at 14-15? her brother didn't look like a child (as he is Jiwoo's age) so i concluded she's 20-21. & took over (when her parents died at a young age - like 16-17)
Guys do you know how old Jiyoung is?