Jack thought about what he should do to test the guy out, but then he thought of another option he should add to the gun. How funny would it be to de-age a douchebag's dick? Or maybe de-age a bitch's tits? That would be funny to see, and it was making him horny too. So he added an option to choose a body part. After he wished that he noticed a new screen popped up on the gun. It was currently set to "Body". He flipped through the screen and noticed a bunch of options including: head, arms, legs, chest, ass, crotch, mind, etc.
To test it out, he figured what better text subject then himself. He quickly let down his pants and boxers as his hard on dick was let loose. "Sorry buddy, but I need to check this out." He selected "crotch" and then set it to age regression, physically, and aware. He then aimed it at his boner and clicked the gun. Soon he could see that his hard on was getting smaller. As his balls shrunk down he noticed his cock going limp, as once his balls "undropped", he had no reason to have an erection. He continued to shrink his little wee-wee until it was about the size of a jelly bean. His penis had to be about six months old.
"This is so cool!" he said as he flicked his little pecker. It was weird touching his baby dick and not having any sexual arousal whatsover. But then all of a sudden, he started pissing himself. Apparently he had the bladder control of a baby as well. He quickly reverted the gun and clicked as he watched his junk grow back. He stopped it once he returned it to around 16 years old. Why not have a teenage dick on his adult body?
"This is great. Now what should I do? Find somebody else to test this on, or continue experimenting on myself?"