You were worried, as you stared at your dad, now a weird and grotesque mix of man and bat. did the transformation have something to do with Dad's wish?
Suddenly, before you realized it, Dad started to shrink! He gasped, as he saw you get taller and taller. Dad soon found himself small and stark naked, as his undies were now far too big to wear. He let out a loud squeak as he covered his fur-covered penis with one of his bat wing arms.