Yvette has her slave on a new furniture, called the facesitting-bench.
The bench is really high, so she must climb on it.
Once on top, she tries different positions for sitting on his face. because he struggles to much, when he runs out of air, she chains his hands on the bench.
Now she can do, what she wants, he cannot resist.
Her Sitting goes harder, she streches her legs, it's more comfortable for her.... and he must endure all her weight on his face.
Full-weight facecrush is also guaranteed, when she sits like on a saddle with her legs and feet in the air, the bench is so high, her feet cannot touch the ground.