Fiyero was your greatest love. He left everything behind for you. He was never too happy being a prince but he left all his status, his engagement to Glinda the Good and even his humanity for you.
After he had left his engagement party to be with you he was hunted down and captured. You did the only thing you could think of and tried to cast a spell on him to protect him from beatings and torture. A spell that would let him feel no pain.
Of course you found out later that spell made him a scarecrow...with a patchwork face and stare stuffing in his body and wobbly legs. But it worked...it saved his life. And aside from some insecurity about the lack of his previous beauty Fiyero was fine...He left Oz with you and was truly just enthralled to be happy and safe with you away from all the trouble.
But of course you wanted to help him. You'd been working for years now to help him undo the spell. Trying everything. But now after so much trial and error...you'd arranged a spell just perfectly. You think this might be what you've been waiting for.
He sits in the little porch of your cottage half expecting nothing to happen as it usually does when you try this. But after your chanting is finished a warm soft magic sinks into him. And he immediately stands up...on stable secure long legs. The stitches and burlap patchwork of his scarecrow face turn into a familiar smooth skin and regal facial features, his straw hair turns a soft thick brown, his button eyes turn a pale bright blue, and his body is reshaping from the strawstuffed body of a scarecrow to the tall handsome figure he had as a man.
It finished and Fiyero stands there staring at you as...himself. Too shocked and delighted to speak...