The slave is on a thick mat filled with springs, flexibel like a trampoline, reaady for to be treatened with Isabellas ass.
She steps over him and immediatly she drops with her ass down on his chest "uff....ufff"
She bounces and moves back on his throat and face and continues.
She changes between chest throat and face, bouncing higher on the chest, lower on the face, but with occasionally high bouncers on the face....crush...crush ;-)