Seijo ni Uso wa Tsuujinai

Chloe is a money-loving teenager who works as an apprentice priestess in a remote church. At night, she puts her sharp memory and intelligence to use in card games, winning large sums of money. One day, Erald, a wealthy holy knight, visits Chloe with a request: she should become a candidate for sainthood so she can help track down the killer responsible for a death two years earlier.