*...okay that earns you something of a long, scrutinizing look, like he's trying to decide just how much to believe or not. Though, in his case, it's something less of an if and more of a when.... he knows he's putting off the inevitable, that it's eventually literally either drink blood or die. But even so, he's not quite to the point of volunteering that kind of information unasked for, so in the end he says nothing*