"I don't know, dear." Your girlfriend says. You do a double take as you hear the voice come out wrong. You can tell that it's your girlfriend, but her voice sounds. Deep. Manly, even. You can see her eyes bewildered, as her expression looks otherwise normal. You watch as her long hair starts pulling back into her scalp, leaving her with a short, professional men's cut. Her jaw is subtly changing shape as she gasps. "What's happening to me?" She asks.
You're stunned, unable to come up with an explanation. You look to the ground, seeing her tapping her foot impatiently. "What are those?" You ask, clutching your necklace, as it radiates heat on your hand. Her shoes have become a pair of loafers, in a large men's size, and as she taps her foot, the clothing starts to transform up her body: each tap causing just a little more of her clothing to change from the ground up. Her pants becoming a nice, pressed pair of suit pants, and her shirt becoming a white men's button up shirt.
"I can't stop it, help me!" she exclaims, in her manly voice. Right now, other than her haircut and jaw, she still mostly looks female, but that is rapidly changing.