A clear explanation was never given to her. There was no dramatic tale of how she came to the once bright city of men. Minas Morgul had long been under the rule of the Dark Lord, given to his deadliest servant to govern and fortify. Zôrzimril had never seen the Witch-king other than in flight on his fell beast or riding one of the midnight black steeds that were bred in the dark lands. But she knew that the chief of the Nazgûl was her only kin in Arda.

You are the last of that noble line of Númenor. The Mouth of the Dark Lord had once smacked to her in his guttural voice. The Lady of the Dead City, the only living child of man in Minas Morgul.

That was all that she knew of her identity. Perhaps it was all she needed to know. With the coming victory of Dark Lord, it would not matter who she had been or where she was born before she came to Mordor. It only mattered what was intended for her in their new world to come.

To secure the kingdoms of men, alliances must be made with the most powerful. Especially if their little kings can be bought. If they choose to follow our Lord, the greatest of these shall be your mate. 

The Mouth had circled her in the vacant hall. It was the first time she had met with him. She had been a girl, her first moon bleeding had only come that year. But perhaps that was why the Mouth had been sent to Minas Morgul to explain her fate. She was of child bearing age, thus marriageable.

She had met the Mouth many times since that day. The years flowed like the black waters of the poison river outside the city. She was still young, a maiden, but no longer a child.

You will be expected to take an oath of fealty to our Lord in due time. It will bind you in submission to his divine will. He expects nothing of you, but abject obedience. Obey or perish.  

She asked if she would ever meet the black cloaked king that ruled the city, the one that shared her blood. 

The Lord of the Nazgûl will reveal himself to you when you have the eyes to see. Only when you have studied the arts and shed the blood oath to my Lord, then you will witness him in his glory. 

In her youthful curiosity, which she now cringed to consider, she asked if she would ever be brought before the Dark Lord himself.

The Mouth, the Lieutenant of Barad-Dûr itself, laughed long. His commanding voice reverberated off the domed marble ceiling. Even you are not worthy of such a honor, man's child. For all your ancient and noble heritage.

And so, Zôrzimril immersed herself in her studies. 

Within the echoing halls of the abandoned tower, there wasn't much else she could do. And once her abilities began to sharpen, she wanted nothing more than to learn. It was a lonely existence. The howl of the stinking wind through the Morgul Vale beat against the empty halls of the upper city where she dwelt alone in the west wing. The Lord of the Nazgûl occupied the tower, where she was not allowed to venture. She detested the company of orcs. Even the great Uruk Hai were too grotesque for her tastes. They could never know the wonder that her sight gave her outside of their mortal limits.

Perhaps she was a prisoner, but after so many years of living in shadow, she couldn't imagine any other existence. 

Once her eyes were open to the beauty of the Unseen World, the land of Wraiths that transcended her lonely physical realm, her allegiance to the Darkness became complete. Her heart ached to be as fair as the most terrible servants of the Black Lands, for her clumsy flesh to become as fine as winter mist. Perhaps someday, should she prove her loyalty. 

What else could she do, but offer herself in total submission to the Lord of such indescribable loveliness? When the time came, she knew that she would take the blood oath without question. She lusted for the power, the freedom, the ethereal beauty that those spirits possessed.

When her visions of the warrior of Gondor began, she knew that the time was nigh.