When The Phantom of the Opera premiered on Broadway in 1988, Emilie Kouatchou and John Riddle, the production's current Christine Daaé and Raoul, weren't even born! But both grew up loving the musical and dreaming of starring in it one day. Well, that day has arrived and, in Kouatchou's case, she's making history as the first Black performer to play Christine Daaé on Broadway. On stage they play lovers whose relati…