Guess what her underwear looks like

You grin. "My next guess is... What your underwear looks like, down to the shape, material and color."

The wench stiffles a chuckle. By your estimation she looks like she thinks it's a silly game.. But maybe also a little bit kinky. Again, it's been a very, very slow day.

You add in a sweetener to push her over the edge: "furthermore, I am going to bet I get to see if I'm right. If I don't, I lose, even if my guess is correct."

She bites her lip a little. She's clearly salivating at the prospect. It sounds like an automatic victory for her, considering there's no way she's about to show you her underwear.

"Okay wise guy, go ahead"