Miss July's breath-endurance test

Miss July is training her slave in breath-holding, and the best way to do this, is to restrict his breath with her ass.

She binds his hands and starts the game with decending down on his face and start the stop-watch.

Soon he beginns to struggle and fight again her sporty ass on his face, he nearly throw her off....

So she changes the direction, sitting now reverse on his face, his nose deep in her ass-crack, maybe he can hold longer his breath... or maybe she sits better in this way and he has no chance and must hold his breath, because there is not much air in the ass-crack.