She has a young woman’s voice, a friendly face and a police chief’s badge. Her name is “AIko” and she may be Japan’s most unconventional weapon in a war against fraud that cost the country a record US$2 billion last year.AIko – a blend of the abbreviation for artificial intelligence and “ko”, the Japanese feminine name suffix – made her public debut in late May on Osaka Prefectural Police’s YouTube channel, warning viewers about the tactics used by scammers posing as police officers,...