You didn't have a damn clue as to how this was a 'typical activity for lovers', but you didn't have much choice in the matter as she picked herself up from your torso and positioned her rear end above your face and sat down. Only moments later did a warm wind arrive again, entering your nose directly. It caused a similar reaction to before, only this time you couldn't breathe, as she was currently smothering you.
"...You needn't try so hard to force your face further in. Given my wide range of abilities, I can do this as at any point, and given our position, you are free to use it as air." Apparently she thought this was completely normal, and that you were into it at that. Not that you could speak whilst under her, and you also had to embrace the last part of it, as you had no choice but breathe in the following blast. Between the overwhelming smell and this uncomfortable position, you almost wanted to let a tear form.
You did try and hold your breath for as long as possible, but once again you were forced to breath in deeply as she released more foul wind. And based on the muffled noises that sounded like satisfaction alongside her forcing the soft flesh that is bottom even deeper into your face, it would seem she has taken the heavy breathing as a sign of even deeper confirmation.
The only option you could think of was to try saying something, "H-- ki---" However, you can only imagine the lack of sound that actually occurred there, so you decided to increase the volume, unluckily enough, just as she let's it go again, "Hoy..! Yuk-i!" She jumps slightly, possibly due to the sudden vibration you just caused, and as you hoped, she stood up, wondering what you had to say.
So after catching some fresh air, you wanted to question her again, but did you get the chance, or did something unexpected happen..?