My wife and I were talking about something similar to this today. Her and a coworker take great pleasure in arousing their male coworkers. Sometimes it's as simple as both of them eating a lollypop in certain way, sometimes it's an "accidental" cleavage/nip slip. Sometimes it goes even further to them talking about sexual escapades, or on more than one occasion the coworker showing pictures from her phone of her sex play, everything from the all girl threeway she had the night before to the "facial weekend" she and her boy friend had.

But they will do these things just to see the bulge in the guys pants grow. Then laugh evily to themselves when he has to leave suddenly.