A Florist's Dozen

According to feng-shui, every mountain is the residence of a dragon. The peninsular part of Hong Kong, known as Kowloon or “Nine Dragons,” takes its name from this principle. But there aren't nine mountains in Kowloon—only eight. Centuries ago, an astute counselor complimented a visiting emperor by calling him “the ninth dragon” (or mountain)—hence Nine Dragons.
Including someone in a flattering way, when you are enumerating something, has now become a common conceit. Hong Kong florists use it to great effect every Valentine's Day. You order a dozen roses, but the recipient only gets 11. Challenge the florist and you will be told that your beloved herself is “the twelfth rose.” This is both custom and commerce coming together in a beautiful segue. From every twelve dozen roses a florist buys wholesale, they're making up a dozen that sell for 100% profit.
I don't think it's a conceit that can be applied too liberally (“Why are there only five bottles, sir?” It's because you are the sixth Heineken”). But I point it out in case anyone from overseas paid for a dozen roses to be sent to their Valentine in Hong Kong yesterday, and is mildly curious as to why they arrived one short. She was the twelfth rose. And you were the 1,464,309th dupe.