With the watch on your wrist, you leave the shop. Despite your uncertainty, you're very anxious to use the watch to swap yourself. However, you decide to err on the side of caution, and head to the park to test it on other people, first.
Arriving and sitting on a bench, you look over the instructions, once more. "When selected and the button pushed you must only picture two things that are swapped and push the button." So the watch can read your mind? You wonder how technology like this works, but decide to just write it off as "magic" and look around for targets.
Walking in your direction are a man and his wife. Perfect, this'll allow you to see if either notice the changes. You make sure the watch's third hand is pointing to 3 o'clock. Using your own genderbending as inspiration, you imagine the wife swapping with the man's genitals, and press the button in the middle of the watch.
In the blink of an eye, in place of the woman, you see... what appears to be a human-sized penis masquerading as a woman. The head of the penis is lowered to face foward, giving you a clear view of its face. Aside from a pair of eyes, it resembles a regular penis head. The penis is even speaking through the vertical slit. It appears to have hair like a regular woman, though you question whether it's a wig. As the couple get closer, you notice a pair of nostrils above the slit. You'd imagine a pair of earholes are hidden under its hair.
The penis is wearing a tank top with shorts and sneakers, giving you a decent view of its body. Its thick neck extends into its shaft-like body, still with a pair of breasts. And although it appears to have the arms and legs as a typical human, the way they flex implies a lack of a skeleton.
The man and penis walk by, continuing their conversation as though everything was normal. The watch DID promise that everyone except the user would be unaware of any changes. However, the penis, noticing that you had been staring at it, stopped and turned toward you, glaring. "Yes, I know, I look like a penis. You probably don't see this sort of thing, everyday. Well, I do. Every time I look in the mirror. And you know what? I like how I look! And so does my husband! So here!" It slaps your cheek with its hand. The lack of skeleton didn't make that hurt any less. "There, now you can say you've been dick-slapped by the prettiest woman in the world." The husband laughs, and the two walk off.
Well, that was a painful revelation. You had expected that a lack of awareness would mean that nobody would see a walking penis as anything out of the ordinary. Nope, it... or rather, "she" really was a woman who looked like a penis! Honestly, you were kinda jealous. You briefly considered using the watch to swap with her, but that wouldn't give you her body, just her personality and life.
That made you wonder, what happened to the former woman? You assumed that the husband now sported a penis that looked like the woman. Of course, the husband was wearing pants, so you couldn't really see the end result.