Muffocation

The act of performing cunnilingus until one passes out from shortage of breath.

I was eating her out for so long that I suffered from muffocation.

Muffocating

An individual dying or being brought close to death by the restriction of air due to their airway being covered by a female's genitals.

"Jon gasped for breath. His life flashed before his eyes. He'd been having such a good time but now his girlfriend was muffocating him.'