I feel like the HaJoon is Chairman's only son and Siwon is the child of Chairman's wife. So Hajoon and Siwoon might be step siblings. It shows that Hajoon doesn't have any power yet and the chairman and his wife doesn't care much about Siwon and though Hajoon cares, he can't oppose his dad. That's what I git to understand.
YOHAN AND YOON JAY IS MINE
