Adding on to what I already see commented:
- fisting (me OR them)
- smegma (was on a second date with a man and he legit whispered in my ear at the bar "I haven't washed him since we last went out, it's like prelube" and implied I needed to do it for him... NOOOOOOOO... BARF BARF BARF.. I literally turned green and he tried to play it off as a joke but I was out... jesus just thinking about it is making me queasy)
- anything without consent
- pegging
- open relationships
- swallowing (I've tried, I literally puked, never need to do it again thanks)