The co-worker reviewing the document seems distracted, much like you are by her. You observe she's dressed a bit more daring, so you assume she has plans. You steal a glance of her formfitting skirt, wondering if she's wearing anything underneath, but careful not to be caught staring.
You daydream about her, fantasizing about her hot date. Fancy restaurant, a movie, or straight to the hotel? Vanilla or kinky sex? Maybe something entirely different, whatever it is, surely more colorful than the dull office.
You can't be upset, you hold out hope that one day she'll have plans with you.