My Horse is Him!!!!

A boy named Saveion is a shape shifter, but he shapes into a horse not wolf like normal storys go! When, Willow about 15 years old finds him after she ran away. She take scare of him, but then she starts shifting into a White Rare Stalion will Saveion beable to protect her from other males!? Or will she be taken by the males during horses matting season?! You'll just have to find out!!!