"Here, let's give her this. Should stop the transformation from progressing." Danny handed Sara a tube of the "Human" vial.
Sara poured it in, and watched as it took effect. Mary's snout and ears shrunk, pulling back into her skull. Her body lost mass, but retained an animal cast to it. Her hooves and tail remained unchanged. But her pussy shrinks, as do her nipples. The nubs that were the beginnings of an udder disappear.
Mary's testicles and penis shrink to a more manageable size, but are still large on a human. Still black and covered in hair, her balls are the size of peaches, and her penis is about eight inches flaccid instead of a full foot. Her chest recedes a bit, and as soon as that's done changing, her arms and legs start to look more human.
When the transformation is over, Sara is sad to see her cow playmate is more human looking. But at least Mary's mind is clearer. Danny nods in approval once the change is done, and leaves to document Mary's changes. Sara looms over head as Mary begins to wake