Stefanie has her slave on a high bench and sits on him like on a horse, means mostly fullweight.
In the beginning she sits on his throat and teases him with a boot in the face.
Then she moves foreward right on his face.
Sitting so good she decides to make a smoking break with longer sitting periods.
She want to use him as ashtray and lifts her ass so he gets some air and ash.
The she moves again on the face, clamps him good with her legs on each side.