"Sell her to you?" Richard looked at Sherlock and asked.
"Mhm, sell her to me," Sherlock nodded, explaining, "A few days ago, a person, well, let's just call him an ordinary friend, found me. He said he had saved a pitiable girl from the auction, asking if I was interested.
You know me, I can't stand to see girls suffer, especially pretty girls. How could I just watch Lucia remain in another's hands—a person who was not exactly kind to women. So I spent nine thousand gold coins to buy Lucia from him."
"Nine thousand gold coins?"
"Yes, nine thousand gold coins," Sherlock nodded and smiled, "For a girl as beautiful, adorable, kind, intelligent, and capable as Lucia, the fact that he only asked for nine thousand gold coins shows he didn't try to extort me. Perhaps he wanted to forge a deep friendship with me."
Richard: "..." Acquired for four thousand five hundred gold coins and flipped for nine thousand gold coins—truly not an extortion.