Luke is an honest and trustworthy individual. These qualities make him an excellent broker for all of his clients.
He is also a cunning man, always ensuring the highest possible profit from all of his transactions.
Luke was born the son of a broker. One of his father's clients was Gozer. This led to Luke making connections to the Harz Duchy through Gozer. He eventually took over as Gozer's personal broker.
Luke and Michio first met when the latter entered the guild looking for a broker. Michio decided to hire Luke; unknown to the latter, it was because the former's Purchase Negotiation and Discount Negotiation skills would work on him.
Luke is Michio's personal broker. Luke is a trustworthy broker, getting what Michio orders without giving him fake items. Luke seems to see Michio as a good customer; someone who always has more orders placed and sometimes sells valuable equipment.
Luke seems to be well acquainted with Gozer, as his father was Gozer's personal broker in the past.