A very broad theme, but workable

You play a shop keeper who specializes in equipment and items for adventurers. Your goal is to speak to your patrons and convince them they need a item. Whenever you speak to a adventurer, you can select the kind of conversation you want to have and then fill the spaces using a list of verbs.  Depending on if you made a sale or not you gain points based on how far a leap you made (Like getting a warrior to buy a staff) and how well you catered to their traits (possibly randomly generated?). Points can be used to buy enhancements (like shopping music, a larger vocabulary, etc).

Gonna start making a quick and dirty prototype after a snack run!