The slave is used by Goddess Vanny as a little horse. On this old horse she can ride around just as she wants. Goddess Vanny swings her leg over his back and pushes him forward! Run little horse, run! Faster and faster! She drives her old horse to the edge of exhaustion and demands everything from him! Don't stand still! It goes on and on for the little horse! He carries his mistress Goddess Vanny around on his back and obeys her as a good pony should. Goddess Vanny beats him once more to keep it that way! She takes the whip and hits him again and again. A good little horse has to be able to stand that too... now move!
Mistress Zora's slave trots after her like an old donkey until she doesn't feel like walking anymore and straddles his back. Fot as long as she wants, the slave will let her ride on his back. Too bad for him that Zora is bored on his back and already has an idea how she can humiliate him further. She stops her pony and dismounts him. She makes him take off her sneakers then pushes his face into them and orders him to inhale deeply. Does that improve his ability to be a good slave pony?! Mistress Zora tries it out and lets him breathe the scent!
For Angelina it's just normal to train her slaves to be a human pony during their slave training. As a young dominatrix she knows exactly how to make submissive slaves follow her orders. Just like this slave should feel honored to be allowed to serve this goddess as a pony. And when her pony can't take it anymore? Then Angelina will just make it move with some kicks!