"You had best consider it permanent." He smiles, "Technically, you can become male again, but I was a pony girl for years and it was only an accident that you allowed me to switch bodies with you."
"And just how did you manage that?" you stifle the urge to beg him to tell you.
"Actually I am not completely sure," he confesses, "And I don't know if the pony girl who tricked me knew that much either. But she seemed to feel she had to tell me, and so I had best tell you what I know or suspect.
"First, you have got to get me or some other man to say he wants your body, and you have to say you want his. I don't think the words have to be exact, but they do need to possibly mean he would like to trade bodies with you. As you already know, he doesn't actually have to mean that, just saying something that can be twisted to mean that. But if he says anything that makes it clear he doesn't want to trade, it's all off and you will need to start over.
"Then you need to make love with him. Not just have sex. You both need to climax and you at least have to be very pleased with him. I'm not sure what that means. I figure it means a guy who gets you hot. But I doubt you will get anywhere trying to trick an enemy.
"I do know you will want to be a very kind master to whoever you do trick if you do manage it. The ponygirl who tricked me begged me to let him prove that, but I was so mad I insisted on leaving and he reluctantly let me. Of course I was enslaved within a week and have had to work hard ever since. So now I want to be a very kind master for you and you will have the best life any ponygirl can hope for. And you had best let me. This is a very dangerous city for a ponygirl on her own. If you insist, I will free you, but you would be much better off being my slave."
"I would be even better off if we just made love again right now and changed back to myself." you counter.
"Alas my liver" he actually looks sorry as he says this, "I do love you, but I sorrow to say I do not love you that much to give up all your wealth."
"But I would be a good master for you." you argue...
"I do not doubt it, my pretty one." he answers, "But we both agree it is better to be male, and so I must deny you this favor. Be satisfied with a comfortable life with a kind master."
"I am not going to let you rob me that easily." you answer.
"But what can you do?" the thief with your face responds, "I know all the ways you can reverse this magic and there is no way you can trick me into changing back. All now see you as a mere ponygirl, while I have all your riches at my beck and call. Accept that I will treat you kindly and be happy.
"But right now..." he bends and checks your leg, which is painful, "alas, I had hopped the magic would also cure you. But such is not to be. So let us continue on to your mage friend.. Now my friend, and get you cured..." With that he easily picks you up and starts to carry you, and you are distressed to find you rather like this, and are leaning against "your" powerful chest for reasons besides comfort.