It was a silent auction.
The auctioneer flashed numbers on a giant screen while pointing at the bidders holding placards to declare they were still 'in'. Gradually the placards fell away until only Harold and Jasfoup were left holding placards.
Harold glared at the oblivious Jasfoup as the numbers clocked higher. Finally he gave up and left Jasfoup with the winning bid.
"What were you thinking off?" he asked afterward. "You were bidding against me. We could have got that fifth century Septuagint for half the price."
"Not at all, Harold," said the demon. "You're not my only client, you know."