Tubgirl*, that's why.
*An old internet shock meme, along the lines of Goatse, Lemon Party, and later Two Girls One Cup.
Tangent but it is hot as fuck to see your bf's face covered in saliva after sucking you off sloppy style
If you don't mind me asking, what does she like about it? Is it like a dom thing where she likes being serviced, or is it like one of those double sided straps so she could still feel it?
I'm literally scared this would happen if I were to attempt to give head lol I got a really bad gag reflex