Continuity mistake: When Charlotte leaves dinner to argue with Trey she leaves her napkin on the table, but it disappears a shot later. A shot later it reappears.
Continuity mistake: When the girls have dinner, Carrie has a glass in her hand that swaps to a napkin a shot later.
Continuity mistake: When Trey shows up at the diner his hand is away from Charlotte or cuddling her arm, depending on the shot.
Continuity mistake: After Charlotte tells Trey that the girls are coming over to dinner, he is holding a cup in one shot and a newspaper a shot later.
Continuity mistake: While having breakfast, Trey folds the newspaper and then the shot swaps to an aerial angle where the newspaper is back to unfolded.
Answer: A popular brand of sexual lubricant. See http://www.k-y.com/index.jsp.
J I Cohen