The origins of the 15, 30, and 40 scores in tennis are believed to be medieval French. It is possible that a clock face was used on court, with a quarter move of the hand to indicate a score of 15, 30, and 45. When the hand moved to 60, the game was over.
Olivia thought the nightmare was over when the cult learned that she wasn't a virgin. But she quickly learned that they had other rituals than just sacrifice