Nothing ventured, nothing gained right? You select "bust" and replace it with the word "udder" just to see if it is even possible. This way there can be no "coincidences" or misconception behind it if it works. You also set it up so that only you and Emma know the difference. You are shamfully hoping to see something interesting happen if/when Emma discovers her new appendage.
You confirm the edit and look up to find that not only has the front of the front desk been replaced by transparent glass, but it now also frames the dangling pink sack between Emma's splayed thighs. The chair she is using also seems to now be closer in shape to a public toilet seat than a desk chair, as her udder is hanging down where a chair's center normally should be.
You are curious as to what large constitutes as, seeing how modest is apparently quite big already. While you think this, Emma's face turns deep red and she begins to panic at her sudden growth if an udder between her legs. This is only made worse by the realization that her once pencil skirt is now just a strip of fabric covering only a few inches to either side of her ass crack. Her entire front and crotch are completely out in the open, with just her "modest" pink udder to cover them up.
You are cheering on the inside, but have the forethought to not react to the sudden shift in reality. Instead, you attempt to play it off as nothing and approach the front desk. Emma doesn't seem yet aware that her desk has become see-through either.
"Something the matter Emma? Your face is awfully red. Are you feeling alright?" You say in your most innocent tone of voice.
"Huh! Oh, um yeah I'm fine. Hehe" quickly lies Emma. She clearly is hoping to hide her udder, but you have different plans for that.
"So if it's alright with you, can I as a question. And I hope I am not offending you by doing so. I am simply curious is all. But... do you need to like, milk your udder, or is it just there? Oh, but if you don't feel comfortable answering, that is completely OK too." You say.
Emma faints from the built up stress.
"Well shit" you grumble to yourself as you catch her from falling fully out of her chair. You take her into the back room and lay her down on the breakroom couch. You take out your phone to call someone, then remember the app and generate a sentance about her.
"Emma has fainted from being overwhelmed by the sudden growth of an udder between her legs, and by the realization that everyone somehow knows about it."
You change "fainted" to "recovered" and confirm it. Emma immediately regains consciousness and sits up. She is significantly more calm now than from what she was before. She notices you standing there and turns red again. She tries to cover up her udder but to no avail.
"Are you alright Emma? You just passed out suddenly out of nowhere. You don't look well, so maybe you should call in sick or something."
"No, are you alright? Do you not see that I have this, this thing between my legs?"
"Your udder? What about it?"
"What? I'm not supposed to have it. The hell is up with you?"
"But you've always had it. I get that it is very different from normal girls, but you never seemed to mind having it, before now that is."
"Are you fucking with me right now?"
"Yeah."
"Of course you're no-...? Did you just say yeah?"
"Uh-huh. I'm messing with you right now. Sorry about that. I know your udder isn't normal, and that you didn't have it before just a few minutes ago. And I am also the one who gave it to you. Sorry. I was testing something out, and took it a bit too far. I can fix it though, probably." You apologize. You've had your fun, and now it is time to make things right.
You generate a new sentance.
"Emma is pissed about the udder on her body that now she knows you somehow added."
"Oof. Alright good news and bad news. The good news is that well, I can remove it. The bad news is that you won't like it" you say.
"I don't care, just get rid of it!"
"Alright, just remember that you asked me to do this." You swap out the word "added" for "removed" and hit enter, making sure she is also aware of what is happening.
Emma, now udderless once again, is anything but happy. "Why?" She asks.
"Why... what? The udder is gone now. Just like you asked." You repeat, somewhat confused.
"But why does that now make me feel so pissed off? Why do I now want it back? Why am I mad at you for removing it after I just asked you to?" Asks Emma, now very confused by her own emotions.
"It's a lot to explain. But I can promise you this. If you hear me out, I will do what I can to make it up to you. Deal?"
"Fuck... fine, deal. But you better have a good reason."
You show Emma the app and explain it to her. You even let her make a test edit to prove it works. And now that she is in on it, her interest has completely outweighed her anger in you. She even admits that she likely would have done something similar if she had been in your shoes, though she definitly wouldn't have left the target aware.
"Alright, so about making this up to me. Let me do something to you" grins Emma while picking up your phone. "Hey, fine, but nothing super risky or changing who I am or my memories alright. And preferably something that can be undone easily enough too."