While having your feet grow was pretty hot, Mike not realizing anything is wrong gave you a new idea.
You've heard the rumors about what a stud he is around campus, and decide you want to know what all the buzz is about. You point the device and instantly you notice a tightness in your pants. Your current underwear wasn't ready for Mike's footlong python. At best, you were 5 inches erect.
Now you're sporting a noticeable bulge and your balls feel bigger too. Mike's alpha testosterone starts flowing through you and you realize you're getting horny and want to fuck the next girl that comes your way. That's when you realize that swapping your genitals has also switched yours and Mike's sexuality.
While you're mid thought, Mike says to you, "Dude, I thought you said you didn't switch anything else out." Confused, you ask him what he means. "All of your underwear and jockstraps are all over my room, can you come get them, I don't really feel comfortable as some of them seem... stained."
You go pick up what is actually Mike's old underwear and get your first whiff of your new musky smell. It begins to turn you on a bit more when you decide to...