Because he did not like to be corrected and to do the right thing, this slave ended up messing a lot and that is how he pissed off lady Chrissy as well as lady Missy. The mistresses turned him into a human pony to punish him. When he tried to refuse, he was forcefully gagged and he was also slapped. He was humiliated and in a lot of pain. And he still had to be their human pony.