Impure path to the top

You are an orphan girl that worked her hardest to get into the cathedral to have a better future. However the amount of merits and missions needed to climb up the ranks get harder and harder . Only those with connections and money have had the opportunity to ascend the ranks . You were having trouble keeping your current status even when working your hardest . But it all changed when you found dark magic . While said to be used by evil you need it to continue your path in life . What’s a little bad to get to the end.