The young woman in the stands simply sighed, turned her head and sat there, looking impossibly composed, while 15 million strangers fell briefly in love with someone who had never existed. She was, according to the caption accompanying one of many posts, “the average Korean woman”. Her admirers quickly crowned her a “baseball goddess”, analysing her every feature with the forensic enthusiasm reserved for internet obsessions, as the five-second clip went viral across South Korea’s online...