What gave me chills was that the line before this. "I have seen it", because if you pass a passive empathy check I think, your own brain will chime in to warn you "Something terrible. Worse than what you have seen." right before this. And considering how well we know Harry by this point in the game, if his brain is warning him that something is worse than anything that he has experienced, that is bad. Harry has experienced some pretty terrible stuff and his brain is predisposed to focus on that and make an even bigger deal out of his personal problems. So the little warning that "Whatever this man has seen is worse than anything that has ever happened to you" from your own brain sets me up for some cosmic horror level shit that this line then beautifully delivers on.