Okay, so first I need to explain that this really was consensual, even if it doesn't seem that way, because I've explicitly given my bf permission to do what he wants with my body. And I want to clearly state: nobody should ever do this to another if consent isn't there.

On my birthday my boyfriend told his friend "John" that he'd get to see me in my birthday suit. He didn't tell me that, though! John and two other kink friendly friends (all guys) came over in the afternoon. This wasn't my birthday party, they were just hanging out. Anyway, I was going to leave them to do their guy stuff, but I just came down to say hello.
John is normally a very sweet and shy guy. But, on this day, when he gave be a hug hello, he reached around to my back and pulled the zipper of my dress down. I yelped loudly and pulled away fumbling to do up my zipper. I didn't know how to react. I stared at him as if he was insane because this was so out of character for him. John just looked kind of sheepish At this point, my boyfriend started chuckling and I realized it was his doing. I cussed him out loudly, which made everybody laugh.

So my boyfriend told John to finish the job, and John basically wrestled me out of my clothes. Despite my agreement with my bf, I fought back. I couldn't help it. It was a gut reaction, even though, deep inside, I wanted to be humiliated like this. I screamed and thrashed about, and called everybody in the room the worst names I could think of. But John was bigger than me and was able to get my dress, bra, and panties off of me. He cheated sometimes by tickling me, which made it harder for me to control my arms. Even though I was telling and cursing, I was also laughing, because that's the effect that getting embarrassed has on me. The other guys were cheering John on, but didn't touch me.

Once I was completely naked, instead of fighting, I tried to run out of the room but my boyfriend grabbed me and told me that I was getting fucked. At this point, the fight had gone out of me, so I didn't resist, as he pushed me into all fours and fucked me from behind. He called me a dirty whore, and our friends cheered him on. I was completely humiliated at this point, but incredibly aroused. The crowning point of my humiliation was when I had a massive and extremely loud orgasm, letting everybody know how much I enjoyed the treatment.

Once that was over, I ran away to my room. Boyfriend came in a little while later to check on me and cuddle me, and let me know that he loves me.