NC for this as I've told this story to people in real life so its outing. TW this describes graphic non consensual sex acts.
I went on a date once with a guy off an app- it was clearly a hook up, neither one of us were looking for anything more, all fine and consensual. We went for a few drinks first and aside from the fact we clearly didn't have much in common beyond wanting to sleep together, he seemed fine and normal.
We went back to mine and had sex- he was on top and and then moved up so I could give him oral sex. He straddled me while doing so, pinning my arms to my sides, and choking me round my neck with both hands. I couldn't move (he was much bigger than me) and couldn't breathe properly- I couldn't say anything either due to his penis being in my mouth. I was trying to communicate to him with my eyes that I was struggling to breathe, but as we were total strangers communicating in a non verbal way was very difficult as we didn't know or were able to read one another.
After he finished I told him that I didn't want to do that and that he should have stopped. He was genuinely surprised that I wasn't into it.
I don't necessarily think he had bad intentions (although I am not minimising that he sexually assaulted me) but it was really scary being in that situation, especially with a total stranger.