As signy says. People think different things when it comes to facesitting.
Facesitting, smothering, ass worship, oral servitude etc.
I recall someone on another forum saying his requested facesitting session went badly wrong.
“She sat on my face and I couldn’t breath” he said.
What he should have asked for was,
“Can you kneel over my face so I can lick your pussy”
Instead of assuming (wrongly in this case) facesitting meant just that.