I can’t remember the name of an old story. its about a guy who finds a website or an email that can change people with nano bots I think when they are injected. He orders two one for him and one to sneakily inject into his wife but it back fires because she found his history and changed both of their vials. A weird fact I remember is that both times the charges of the vials and changes cleared out their bank accounts exactly to what they had. I gained this information from another user “I thought it was on Overflowingbra but I couldn’t find it. As I recall he finds a website that allow sells something that changes a person into what you want. he orders one for his girlfriend and one for him. He takes it and gives one to her. He turns into a hot bimbo and she comes out of the bathroom with a penis. “He” then falls on his butt and finds that the fall is cushioned but his larger but. He then has sex with his girlfriend.” im not sure where else to look but if there is a better suited subreddit ill post there instead
Source: reddit.com/r/Erotica/comments/5r0n60/been_looking_for_a_story_not_sure_if_this_is_the