Him.

His name was Jok Do Hee. He had a sister, Ha Sun Hee, who passed away 5 months after birth due to heart failure. He lived a normal, humane like life. He should've known, no ones life is normal. On April 18th 2014, his life changed the day he met Go Dok. He was a CEO of a very suspicious business with plenty of murders and scandals involved. He offered him lots of money and a p,ace to stay, on one, small condition. To murder everyone he ever loved. He had a wife and two children. He declined the offer, and though it was the end. He was very very wrong. Almost five years later, his wife and children were found, dead. He was framed, and everyone believed it was a homicide. I guess by now you know who did it. Wrong. Whoever your thinking right now is absolutely incorrect.