Dismiss them for the night

You look at the four shocked women, and decide that tonight may not be the best to begin with your plans. They should be allowed to spend the night in anticipation, searching futilely for ways to remove the collars. Morning would present you a glorious array of **** and haunted looks.

"Go now to your quarters. You will return in the morning to this room, dressed exactly as you are. You will meet around this table where you will find food. Eat everything you are given, no more or less. Then remain here until I join you." You finish with a derisive laugh and gesture, shooing the women towards their rooms. None moves. You smile, having expected the resistance. You raise an eyebrow. "So defiant? Come now, surely you know nothing will come of it." You gesture again, and this time each girl finds her body slowly carrying her backwards, in spite of her mental demands to stop. You smile again as they all disappear into their respective rooms, and your mental command locks them in. Then you disappear again into the upper regions of the tower.

The following morning, the four women find their doors unlocked and food laid out. They eat in silence, each digesting the hardy if unappetizing food and the situation they found themselves in. You appear once again in their midst as they finish. "Good morning, ladies. I feel..." You snap a small bolt of lightning from one finger to another "... refreshed. I see some of you were trying to use your powers last night; I trust you are satisfactorily dissuaded. But now I sense you are curious. My comings and goings are indeed unusual, yes; and I imagine that none of you has had the chance to examine the further heights of my humble abode. Well, we ought to change that. Would anyone like to begin?"