[BBB]

You said you hadn't hit a character limit, so it wasn't clear how long is too long. I said latex so that it wouldn't do a mylar balloon. And "small-breasted" is important to get the contrast of before and after. It's not an inherently R-rated term... I'm curious what it actually does if you try. Does it generate or not? If it doesn't, does it identify the word(s) it objects to, or do you have to guess?

Second attempt:
A skinny young woman in a small crop top blows up a balloon at home. Then she strains to blow harder. Then the balloon deflates into her mouth and her bust expands. She looks down at her more voluptuous figure, shocked but pleased about the change.

P.S. If you didn't know, the three videos in your top post are not available anymore. So if you didn't take them down, streamable may have a time limit.