Similar to other definitions, the bucking bronco
is when you are fucking your girl doggy style, you then make
a smart comment(ex. "I have
AIDS" or "Your sister was better" and see how long you can stay on for.
You are banging a random chick you met that
night, doggy style. While it's all goin on you whisper in her ear,"I have AIDS," then let the ride begin and see how long
you can stay on that
bucking bronco for.