The person Merem called Princess. Needless to say, it was that person.
To True Ancestors, she was Hades, but Merem was quite fond of her.
Merem seemed to assist the Princess in chores such as trading gold for money, booking plane tickets, etc.
The Princess did not really know what to do with Merem’s unconditional affection, but without him, she would have much trouble roaming around the world.
During this story, she was peacefully slumbering in her hideout.

Yoi No Myoujou: Talk.

Loved gold color, despised black.
The Princess that the Priest (Merem) spoke about, of course it was that person. The kid only talked about her, it seemed that he never grew up.
On the one hand, the Princess was not very good at dealing with the Priest, making his friendly gestures seemed unacknowledged. On the other hand, the Black Princess loved the Priest very much. She loved him so much that she was hesitating whether or not to just eat him.

Character Material: Prelude Explanation