I would like to open here my "theory of conspiracy".
Very early in the game, when complete you first task for the queen Merneith, she promise you an enjoyable reward stay in her thermae. When you go there as Zaton alone, she will offer you to pick one her personal slaves for yourself. You can either pick both, pick one on the left or pick one on the right. If you choose pick both, the queen will deny it, then you need to pick the left or the right slave.
The thing is, both choices has variables marks on the scripts, meaning that these choices could have consequences later.
But, my theory is about the slaves who will choose. The one on the left is unexperienced and she show quite unconfortable to handle Zaton's manhood.
And the one on the right show experience and she has no difficult in handle Zaton's manhood.
Both are nice, but is the one on the right who call my attention. Her body format and skin colour is somehow very similar to other characters in the game, like Zahra, Shani and Rabiah.
In my first playthrough I become suspicious that she could be Shani disguised as a queen slave, but after the first scene with Shani, I noticed she was virgin until then, so I discarted that.
My theory of conspiracy: Could this queen slave girl be in fact a Zaton's and Rabiah's daughter, long losted and not knowing by him?