The room has one grate and no coal and a barrel roof built to hold damp in, and it has never been warm in its life.

MalfoidThere is no fire. There is no coal. There is no way to make this room warm before the twenty-eighth.

MioneThere is a way. It is why he specified skin and not blood. He wanted the heat the room needed to be the heat we made.

You are the one who says the obvious thing, because somebody has to and neither of them is going to.