Other stories based on cube idea this: 
First (start): www.deviantart.com/vfrcbvvfrcb…
Frank: www.deviantart.com/vfrcbvvfrcb…

If you like my art, sketches, stories, you can find more like this here (thanks to everyone for the support, it's very important for me): www.patreon.com/greentg

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John saw this trinket in one of these weird shops that his girlfriend loved so much and where he just waited for her to finish choosing all the nonsense for herself. He usually didn't go with her, but not today. Somehow, this store found himself on the road and she persuaded him to come in. The cube immediately caught his attention, it lay along with other things on the store shelves. Everything happened in a split second and it seemed that no one even noticed it, although it was a strange picture. John literally began to be sucked into the cube and after a few seconds he disappeared along with the cube.

When he opened his eyes, he was no longer in the store, but on the street, and for some reason it was not day,
but night, because the lanterns were burning around. He heard music playing from a house nearby, but did not have time to figure out what kind of house it was and what kind of place it was, because he drew attention to new
sensations in the chest area. It was as if someone had tied a heavy weight to his chest and was also holding him down. Lowering his head down, he saw huge dimensions, as it seemed to him from this point of view, the hills that were part of his flesh. He grabbed himself by the grul and felt soft flesh under the fabric with his hand. 

- What ?! What?!

He did not understand for a long time and did not think for a long time, it was important for him to check whether his penis was in place.

- Oh nooo! Heck! Where is my dick !? What the fuck ?! What the hell just happened !? Why… John felt someone touch his shoulder and abruptly fell silent, turning around at the sound of a man's

- Baby, what is it? 

A voice guy in an obviously drunk state looked at him in bewilderment and looked at him attentively John did not know that the cube of probable improbabilities transported him as well as other people who touched him to a parallel universe and placed him in a suitable body. No one knew how a cube chooses shapes and bodies for different people, there was a logic that depended on genetics and biochemistry, but there were a lot of probabilities. Someone the cube settled in the bodies of old people and people with disabilities, and someone even in animals, and many of these people would be glad to be in John's place, but John did not know this. He received the body of a young party girl from a poor family named Veronica, he was still young, but he lost his male part and, most importantly, he lost his father's money, which he always used, and from that moment John needed to adapt to a different life and a different body …

That evening he just ran away from this disco and from Veronica's boyfriend. He tried to ignore his new body, the swaying of his chest, his long hair and these derogatory clothes. It seemed to him that all this was some kind of prank and everyone understands how ridiculous he looks. But that evening, he never managed to find anything about his old life. All his searches were unsuccessful. There was neither John, nor his parents, nor his friends, there was even a different president and much more, which is not surprising for parallel universes.