Spice and Wolf - Season 2 Episode 4 Wolf and the End of the Shallow Thinking

Lawrence realizes that he has to drop the price of pyrite or risk losing Holo to Amati. After receiving the information on Amati's assets, Lawrence finds Amati and proposes a deal based on credit (essentially, a naked short on pyrite), which will result in profit for Amati if the price of pyrite rises or losses if the price of pyrite falls. Amati accepts the deal after Lawrence appeals to his chivalry and causes him to doubt that Holo will agree to his marriage proposal. Unable to enlist Mark's help to purchase the pyrite necessary to pull off the deal, Lawrence turns to the alchemists in the belief that they should have a large amount of pyrite that he can purchase.