"OH my God, that was the best, I can't believe how good it felt being a mannequin and when you took off my arm, gawd, it was almost sexual....like I was made for that, and being used for it was so good" You blink as Sami admits that and then laugh "Oh, so sounds like you want to be a different object then, babe?" she comes over to you and her hand goes down to your crotch, rubbing there "How about turning me into some underwear, nice tight compression shorts to hold your package, hmm?" you squirm and you get a hard on at her touch, but also the thought of that "I dunno babe, I do that and I might not be able to control myself, be a shame to jerk off in you"
But she surprises you again, when she runs a hand along your chin, leaning in, whispering into your ear. "I think it would be a shame NOT to... turn me into shorts, wear me, cream in me, soak my fibers with your cum....do it, you know you want to" gasping, you look at her, then smile, and use the app to turn her into some very snug compression shorts. Stripping down, still erect, you then step into her and slide her up your legs, getting you stiff rod into her form. She is a spandex microfiber that is really snug, really stretchy, and your hard on is a serious bulge in, well, in her form on you! Your hand rubs it, and you feel yourself about to release in no time at all. The feel of the tight shorts, your hand, but most of all, the knowledge these shorts are your girlfriend, trapped on your junk, about to be soaked with your load, and all while she is aware and wants it....
The damp spot under your hand is there before you realize it, and you look down a little embarrassed as it grows in your shorts, in your girlfriend, soaking her. You strip her off, rod still moist, trembling a bit, and you see she is full of white fluid inside her form, soaked into her fibers, making her sticky. You use the app to try and change her back: