The cold wraps around her like arms. She looks over her shoulder not because she feels someone's there—she knows damn well there is, and it bothers her; she studies the "marble" sometimes, but never, never touches it.
He knows because he's watching her. All the time.
Oh, certainly, he could move on. But he doesn't want to.
Because every time she shivers, so does he; he can't understand—having lived the way he did—what it means: this delicious pleasure-pain, velvet-soft, frightening. But he wants more.
So he sticks around. There's not much else to do, when you're dead.