As China moves into Africa—building highways and stadiums, striking oil deals, and opening special economic zones—practitioners of the world’s oldest profession have followed, catering to both Chinese expatriates and locals. Growing African purchasing power helps explain sex migration. Deloitte estimates that Africa’s middle class has tripledin the last over the last three decades. That means more money for imported televisions, imported handbags and, yes, imported sex. Africa is “a new El Dorado for the prostitution business,” Ndjio writes.