You looked at the terminal window on your computer, the script was finally ready. What's more powerful than ancient magics, the darkest depths of science, or the irrationally precise hand of a computer? A combination of all three- with this simple program, you could, in theory- alter reality with a keystroke.
A sense of deflation hit you, despite probably humanities greatest accomplishment under your fingertips, you were still sitting in a remarkably unprofound room, the street outside was strangely parade free, and your girlfriend sat nonplussed in the couch in front of you on her phone. The banality of it in light of your new power was almost insulting, this won't do at all!
You've got to be responsible, though. You can't let it all go to your head. You won't take over the world, maybe just have your own continent, or two. Start small though, take it slow, savor it. Looking up again, your girlfriend sat. She was medium build, despite a pretty face, her figure was nothing to write home about- but, she's worthy of an upgrade.
With a few keystrokes, you watch as she slowly starts to rise out of the couch. Each inch upwards, her thighs flare out two- and her shorts are quickly going to become a problem. Another quick entry, and her shorts are at her ankles.
By this point, she was thoroughly perplexed, having ballooned out what one could guess looks like 100 lbs, rather than let her work up to a panic- you give her another upgrade- a small modification- that she won't be bothered by any normally startling changes she sees. Her face quickly changes to one of excitement, and she stands to get a proper assessment of her growing assets. "It's so big! Thank you so much!" And after some jiggling and posing for her own sake, she curiously presents her new, beachball sized cheeks to you in an unexpected display; giddily she asks- "Can you make it bigger?"
Well, as a matter of fact...