Clip has two views in one, filmed with two cameras on tripods, combined in the same screen.
Kitty steps over her slave and decends with her bare ass right on his face, she shakes her ass so his nose goes deep in her ass-crack... there is definitively no oxygene ;-)
Then she turns around and settles foreward on his face, the same game, no air until he struggles... not really a comfty stool.
So she turns again and sits now reverse on his throat, squeezes nice his windpipe.
But he may like this to much, so she changes again to a no-air-position.