Domnei by James Branch Cabell

Then Perion knew that vain regret had turned his brain, very certainly, for it seemed the door had opened and Dame Melicent herself had come, warily, into the panelled gloomy room. It seemed that Melicent paused in the convulsive brilliancy of the firelight, and stayed thus with vaguely troubled eyes like those of a child newly wakened from sleep.

And it seemed a long while before she told Perion very quietly that she had confessed all to Ayrart de Montors, and had, by reason of de Montors' love for her, so goaded and allured the outcome of their talk -- "ignobly," as she said -- that a clean-handed gentleman would come at three o'clock for Perion de la Forêt, and guide a thief toward unmerited impunity. All this she spoke quite levelly, as one reads aloud from a book; and then, with a signal change of voice, Melicent said: "Yes, that is true enough. Yet why, in reality, do you think I have in my own person come to tell you of it?"