I was that bottom once. I was getting fucked by a guy who was a bit larger than I was used to. I didn't want him to stop, but instinct $%@#$%#$ me to try and pull away. He seemed pissed at this, and said I wasn't getting away, then fucked me even harder. I finally started to feel his pelvis slapping against my ass, deep as he could get. It make me harder and harder the deeper he had reached. I was sooooo thankful that he was a persisting top, who didn't give up. Hell, I even blew my load before he blew his.