"DON'T TOUCH THAT!!"
The surprise of the shout causes you to flinch, startled. The vial you had in your hand quickly jumps out of your hand, going up in the air slightly before crashing down, shattering into hundreds of pieces. Without you noticing, several small fragments of glass, each coated with some of the blasted nail polish, fly upward, flying underneath your skirt and grazing your poorly constrained member.
You back away as if shot from the sound, hoping that nothing bad had happened. You feel a tight pull in your groin, signifying that it wasn't the case. You feel a sharp pain in your gut and a gradual lessening of the tightness around your member. Frantic, you reach into your panties with your good hand, only to be mortified at feeling the last remnant of your malehood get sucked up into you, becoming in a matter of moments a set of fully functional vaginal lips.
Your transformation complete, you look up both in fear, depression and anger at the person who had startled you in the first place....