Wandering through the racks of clothes, you find a pair of lacy black panties. Taking them off the rack, you feel them curiously. they are soft and smooth, like silk. You have an urge to try them on, as you cross dress frequently, but you are worried about video cameras catching you on recording. Reluctantly putting them back, you scour the entire room for cameras. You return to the same spot after finding nothings but a changing room, you grab the panties and head there for extra privacy. Closing the door and locking it, you take off your pants and boxers, leaving them in the corner. Taking a deep breath, you slid your legs into the corresponding holes in the panties, sliding them up your legs, and letting them pull tightly against your crotch. Looking at yourself in the mirror, the ill-fitting garment looks strange on your male body. You are getting pretty turned on at this point, and you are considering jacking off when your crotch starts tingling. thinking that your circulation is being cut off, you reach down and grab the sides of the panties, but you cant seem to get a grip on them! the tingling gets more intense, and you start to feel a bit sick. It feels like the inside of your crotch is blowing up like a ballon, creating a large pocket of air inside your body. When it finishes filling, you feel your testicles getting smaller for a few seconds, then stopping and being pulled against the inside of your scrotum, until they give out a pop and slide inside you. You can feel them burrowing up through your stomach, around the sides of your air sack, and coming to rest around the top of it. You feel the same burrowing sensation again from your balls as it feels like a new tube is growing from each testicle and connecting to the bag. Your scrotum is then pulled tight against your flesh, sealing to become nothing more than smooth skin. Your dick then starts to shrink, and at the same time a hole opens up where your scrotum was. The hole starts to burrow deeper into your body, approaching the air sack, and your dick starts to move downwards on your crotch towards it. As you feel the tunnel complete, it starts to become more complex, creating several flaps, and covering the entrance with two lip like flaps. your dick slides into your new hole, shrinking ot the size of a pea and comes to rest inside. Then, the tingling stops, and you look at yourself in the mirror, shocked at the lack of dick in the panties. You try to take them off again, and suced, revealing a soft, moist vagina.