Earth Supplier in a Magical World

My name is Yan Xing, an Earthling who can freely travel between Earth and a magical world. Elves love the silk I bring them. Orcs love the soap I bring them. Human nobles are crazy about the white porcelain. Dwarves are intoxicated with the alloys they buy from me. Even the undead want to order a top-of-the-line coffin from me to show off their status. One day... angels, dragons, and demons find me. I tell them, "My market is open to all races and creatures. You can pay with gold coins, or with your labor..."