Pain

After six months of arduous training the Registry decides that you should become a pony ****. Due to your superior physiology, you can immediately attend the races, one of them won after the other with no difficulty to you.

Eventually they decide to ban you from the races. But your owner still finds a secret race for you here and there to keep you busy. The only regret of you in this life is the orgasms. Oh, how magnificent those are! As your owner forbids you from them as a form of motivation. You are always promised one after each victory. Only for the reward to be taken away once you crossed the finish line.

Deep down you see through the trick. Yet somehow he always gets you. And you keep winning for him. Only to be tricked again as you get more and more entangled in this vicious cycle.

BAD END: PONY ****