It is from a dialogue in my textbook. 수미 told 수련 if she continues to indulge herself in comics, she will go crazy. And here 수련 replied: 수련: 너 날 저주하는 거지? 사람 놀라게 하지마. 내가 정말 정신이상에 걸리기나 하는 날에는 모두 네 탓이라고 할 것이니 말이야. My translation is: Are you cursing me? Don't make me scared. On the day I really have mental disorder, it is all your fault! In fact the overall meaning is clear, but I want to dig into details. I am not quite sure the meaning of 할 것이니 and 말이야. Would you explain them a little bit? And if possible give me a better translation to convey the nuances?