Rhea

Rhea says something very compelling in DT IV.

In the scene where Cordelia nourishes Rhea with her blood, Rhea says that the way the blood was staining Cordelia's underclothes looked: "like roses, I dream of them often enough, roses in bloom , and what stands among black among 'em at the end of the world". It's intriguing that she could dream of Can-ka No Rey (The Red Fields of None) that surround the Tower. Not to mention the Tower itself.