Modest Figure → Large Gigantic Enormous Voluptuous Massive Tits

Well, as a start... I mean, I am a man, after all, and I've got a bit of a thing for breasts so... I focus on the phrase 'modest figure' and just, as an experiment, kind of think of the idea of bigger breasts... and the prompt takes that idea, then runs away with it as it changes the phrase into 'large gigantic enormous voluptuous massive tits.'

The world jitters and strobes as the angle changes until Sarah's facing me. As it does, the monitor on her desk becomes mounted on the wall, and the lamp turns into a standing lamp hanging over the back of her chair, which becomes larger behind her. Meanwhile, Sarah's hands fall below her desk out of sight as she brings them together on her lap.

Then her lanyard falls into the gaps of her cleavage as her breasts go up a cup size, and then another, and continue expanding until they're each comparable to her head in size if not slightly larger. Despite this, Sarah's shirt remains perfectly modest and fully buttoned, albeit straining somewhat inappropriately against the sheer girth of her tits.

As Sarah leans toward the camera with a soft, mildly mischievous smile and her forearms cup her tits, bringing them slightly closer together to emphasize her cleavage even beneath her shirt... I would swallow if I weren't frozen in time myself. That went well, even if it went further than I expected. So... what do I 'upgrade' next?

(fiance, large gigantic enormous voluptuous massive tits, dark hair, long hair, white shirt, sitting, glasses, lanyard, keyboard, desk)