Hotel Sex with a Stranger

Went on a trip to Berlin this summer and when I was at the bar with my friends one guy caught my eye. I decided to be adventures and said to him no names or contact just pure sex for the night and we never see each other again. He immediately agreed and we went up to my room. I didn't know what he liked because as I said lets not tell each other names and we didn't wanna talk much so I started off the whole thing really slow and vanilla. But it took a turn after few minutes and he started railing me