Your girlfriend, Riley, never imagined her small slender frame expanding into a plump fat mass.
Much to your surprise, you discover a new app installed on your phone called "Girlfriend Gain Meter".
Curious, you open it to reveal a simple meter marked with the text label "Skinny" with the implication that you should drag your finger across it.
You do exactly that, cautiously only dragging it part way. From the other room you hear the distinct yelp of your girlfriend, Riley.
In what seems like seconds she has found her way to you in a panic, expressing how she felt like her skin had swollen.
While she frantically thinks up a plausible explanation, you take a moment to stare at your girlfriend's figure.
Her cheeks have filled out, her shape has pudged a little everywhere, and her shirt has begun to fight off her small, newly, swollen tummy.
"An allergic reaction! That has to be it!" She concludes as you reach for your phone, with devious intent.
She locks eyes with you, briefly wearing the feeling of relief before she realizes that she has no idea what she may be allergic to.
Your finger fills the meter a little more.
Her boobs expand like balloons, and bounce down.
Her shirt recoils up over her stomach as it fills itself to capacity, and her jeans pull at the seams trying to contain her expanding figure.
You look up to see her eyes still locked onto you, with her face contorted into absolute horror.
Knowing that this is probably only going to get worse, the longer you conceal this from her... you reveal your secret.
You look down at the phone with the meter's text label now reading "fat" and turn the screen around to show Riley.
"So I don't have a sudden mystery allergy?" she asks while taking off her jean jacket, which she had clearly out grown.
You shake your head no as she walks towards you, each step stressing the floor boards a little more than you had come to expect.
"and you experimented on my figure- with this "app" twice?", she draws closer.
"... yeah." you sputter out with more guilt than you have ever known.
She stands closer to you than she ever has (you know this because you have never felt her belly bounce into you before she does)
She takes the phone from your hands.
It's quite unfortunate that you feel how fat her fingers got as she takes the phone from your hands, as you debate her next step coming into this new found power that you lost.
Mentally prepared to see your girlfriend, Riley, shrink before your eyes, you look up at her face.
She looks back at you with a smug grin slowly filling her face, as her thumb hovers over your phone.
"And you stopped there?" She lets out a quick devious chuckle and fills the meter with one stroke of her finger.