The slave is trapped in the floor with a hole for his upturned face.
When Jane steps on him, he knows it will be a hard treatening for his face, because he cannot turn away, he's is full exposed... and Jane can be dangerous.
in the beginning she wears sweaty socks, steps on his nose and let him inhale the odor under pressure.
The she feeds him with the socks... he wants to spit out, but to late Jane is again on his face.
Now she plays barefoot with his face, games like toe vs. nose-hole and so on.
Sometimes she gives his face a break and move on his groin area, stands there and watches the reaction of the slave and his cock under fullweight pressure.