Reason.

Kilo was seething with rage when he finished his piece of plea and threat. He hated being so powerless. He hated this guy who pulled his family into this mess. He hated this world that made him do all the things he did. 

Shi Lang saw him and knew that this guy was not lying so he sighed and said, "Kailo, you know that your brother will probably kill himself when you die. Do you want him to get away so easily with the things he has done?" 

Kailo shook his head and said, "I wish to have him suffer in agony and live a life filled with regret." 

Shi Lang nodded and said, "I propose you a deal. How about I get what I want from him and then leave you with the means to keep him alive, without getting in touch with him? Let him know that you are taking care of him but do not show up in front of him. Let him know how much you hate him. How wonderful is that?" 

Kailo looked at the man in front of him and smiled coldly as he said, "I accept."