Hak then asks, “Isn’t that betraying your clan? How am I going to believe that?”
He takes a blow from this. Betraying his clan? He would be betraying his father and brother? Is wishing for Princess Yona to be alive a betrayal to them? He doesn’t know how he’s going to affirm to them for certain that he won’t tell anyone, but he tells them that if he does anything to break his word, no, if he is the least bit suspect, then they can kill him.