My worst experience with a threesome was in Provincetown about 15 years ago. I was walking back to my hotel late at night. Too be honest I had way too much to drink but was horny as fuck and -being shy- had had no luck in the bars. I felt a car pulling up next to me and sort of following me. When I looked over there was this really attractive guy. He asked if I wanted some fun. Must have been the alcohol and horniness but I just hopped in. He drove to the Holiday Inn (a bit out of the center of town if I remember correctly). We got it on and he started to fuck me bareback. Suddenly another guy walked in. I could sense he was the boyfriend. He watched us going at it for a bit, took of his clothes, got on the bed and stuffed his dick in my mouth. The guy who was fucking me started to say he was cumming in my ass and shot his load. Suddenly the other guy pulled his dick out of my mouth and started yelling at the top he was a slut for fucking a stranger bare. And he slapped me hard in the face and yelled at me "And you! Get out!". He got off the bed, picked up my shoes, opened the window and threw them out onto the parking lot. While they were yelling at each other I scrambled to get my clothes and rushed out half naked to find my shoes. There I was in the middle of the night at the parking lot with no taxi in sight... Drunk as I was I managed to get back to my hotel. I thought "never again!". Well, I didn't, not in Provincetown at least ? I can laugh about it now but I do remember I was terrified at the time because of the sudden violance and being left there in the middle of the night out of the center of town.